27 files changed, 766 insertions, 828 deletions

diff --git a/src/Blocks/BlockComparator.h b/src/Blocks/BlockComparator.h
index a2f2d430d..ba939b41f 100644
--- a/src/Blocks/BlockComparator.h
+++ b/src/Blocks/BlockComparator.h
@@ -34,10 +34,13 @@ public:
 		const Vector3i a_CursorPos
 	) override
 	{
+		const auto Meta = a_ChunkInterface.GetBlockMeta(a_BlockPos);
+
 		// Toggle the 3rd bit (addition / subtraction):
-		NIBBLETYPE Meta = a_ChunkInterface.GetBlockMeta(a_BlockPos);
-		Meta ^= 0x04;
-		a_ChunkInterface.SetBlockMeta(a_BlockPos, Meta);
+		a_ChunkInterface.SetBlockMeta(a_BlockPos, Meta ^ 0x04);
+
+		// Update simulators:
+		a_WorldInterface.WakeUpSimulators(a_BlockPos);
 		return true;
 	}
 
@@ -56,6 +59,7 @@ public:
 		UNUSED(a_ChunkInterface);
 		UNUSED(a_BlockFace);
 
+		a_WorldInterface.WakeUpSimulators(a_BlockPos);
 		a_WorldInterface.SendBlockTo(a_BlockPos, a_Player);
 	}
 
@@ -120,15 +124,6 @@ public:
 
 
 
-	inline static bool IsOn(NIBBLETYPE a_Meta)
-	{
-		return ((a_Meta & 0x8) == 0x8);
-	}
-
-
-
-
-
 	inline static Vector3i GetSideCoordinate(Vector3i a_Position, NIBBLETYPE a_Meta, bool a_bInverse)
 	{
 		if (!a_bInverse)
diff --git a/src/Simulator/IncrementalRedstoneSimulator/CommandBlockHandler.h b/src/Simulator/IncrementalRedstoneSimulator/CommandBlockHandler.h
index 6bdd580a9..31a34236c 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/CommandBlockHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/CommandBlockHandler.h
@@ -8,16 +8,13 @@
 
 
 
-class cCommandBlockHandler:
-	public cRedstoneHandler
+class cCommandBlockHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -26,40 +23,29 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating commander the cmdblck (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto Previous = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
+		auto Previous = DataForChunk(a_Chunk).ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
 		if ((Previous.PowerLevel != 0) || (a_PoweringData.PowerLevel == 0))
 		{
 			// If we're already powered or received an update of no power, don't activate
-			return {};
+			return;
 		}
 
-		a_World.DoWithCommandBlockAt(a_Position.x, a_Position.y, a_Position.z, [](cCommandBlockEntity & a_CommandBlock)
-			{
-				a_CommandBlock.Activate();
-				return false;
-			}
-		);
-		return {};
+		a_Chunk.DoWithCommandBlockAt(a_Position, [](cCommandBlockEntity & a_CommandBlock)
+		{
+			a_CommandBlock.Activate();
+			return false;
+		});
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/DoorHandler.h b/src/Simulator/IncrementalRedstoneSimulator/DoorHandler.h
index a22a6ff50..c91886f4e 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/DoorHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/DoorHandler.h
@@ -8,16 +8,13 @@
 
 
 
-class cDoorHandler:
-	public cRedstoneHandler
+class cDoorHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -26,46 +23,27 @@ public:
 		return 0;
 	}
 
-
-
-
-
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-
-
-
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating dori the door (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		if (a_PoweringData != static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, a_PoweringData))
+		cChunkInterface ChunkInterface(a_Chunk.GetWorld()->GetChunkMap());
+		const bool ShouldBeOpen = a_PoweringData.PowerLevel != 0;
+		const auto AbsolutePosition = cChunkDef::RelativeToAbsolute(a_Position, a_Chunk.GetPos());
+		const bool IsOpen = cBlockDoorHandler::IsOpen(ChunkInterface, AbsolutePosition);
+
+		if (ShouldBeOpen != IsOpen)
 		{
-			cChunkInterface ChunkInterface(a_World.GetChunkMap());
-			cBlockDoorHandler::SetOpen(ChunkInterface, a_Position, (a_PoweringData.PowerLevel != 0));
-			a_World.BroadcastSoundParticleEffect(EffectID::SFX_RANDOM_WOODEN_DOOR_OPEN, a_Position, 0);
+			cBlockDoorHandler::SetOpen(ChunkInterface, AbsolutePosition, ShouldBeOpen);
+			a_Chunk.GetWorld()->BroadcastSoundParticleEffect(EffectID::SFX_RANDOM_WOODEN_DOOR_OPEN, AbsolutePosition, 0);
 		}
-
-		return {};
 	}
 
-
-
-
-
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/DropSpenserHandler.h b/src/Simulator/IncrementalRedstoneSimulator/DropSpenserHandler.h
index 131d2eb6c..cee8133d8 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/DropSpenserHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/DropSpenserHandler.h
@@ -8,17 +8,15 @@
 
 
 
-class cDropSpenserHandler:
-	public cRedstoneHandler
+class cDropSpenserHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
 	inline static bool IsActivated(NIBBLETYPE a_Meta)
 	{
 		return (a_Meta & E_META_DROPSPENSER_ACTIVATED) != 0;
 	}
+
 	inline static NIBBLETYPE SetActivationState(NIBBLETYPE a_Meta, bool IsOn)
 	{
 		if (IsOn)
@@ -31,9 +29,9 @@ public:
 		}
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -42,45 +40,34 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating spencer the dropspenser (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
-		bool IsPoweredNow = (a_PoweringData.PowerLevel > 0);
-		bool WasPoweredPreviously = IsActivated(a_Meta);
+
+		const bool IsPoweredNow = (a_PoweringData.PowerLevel > 0);
+		const bool WasPoweredPreviously = IsActivated(a_Meta);
+
 		if (IsPoweredNow && !WasPoweredPreviously)
 		{
-			a_World.DoWithDropSpenserAt(a_Position.x, a_Position.y, a_Position.z, [](cDropSpenserEntity & a_DropSpenser)
-				{
-					a_DropSpenser.Activate();
-					return false;
-				}
-			);
+			a_Chunk.DoWithDropSpenserAt(a_Position, [](cDropSpenserEntity & a_DropSpenser)
+			{
+				a_DropSpenser.Activate();
+				return false;
+			});
 		}
 
 		// Update the internal dropspenser state if necessary
 		if (IsPoweredNow != WasPoweredPreviously)
 		{
-			a_World.SetBlockMeta(a_Position, SetActivationState(a_Meta, IsPoweredNow));
+			a_Chunk.SetMeta(a_Position, SetActivationState(a_Meta, IsPoweredNow));
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/HopperHandler.h b/src/Simulator/IncrementalRedstoneSimulator/HopperHandler.h
index 32b615ffa..2f2e5b129 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/HopperHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/HopperHandler.h
@@ -8,16 +8,13 @@
 
 
 
-class cHopperHandler:
-	public cRedstoneHandler
+class cHopperHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -26,39 +23,28 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
-	{
-		// LOGD("Evaluating commander the cmdblck (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
+		// LOGD("Evaluating holey the hopper (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto Previous = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
-		if (Previous.PowerLevel != a_PoweringData.PowerLevel)
+		auto Previous = DataForChunk(a_Chunk).ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
+		if (Previous.PowerLevel == a_PoweringData.PowerLevel)
 		{
-			return {};
+			return;
 		}
 
-		a_World.DoWithHopperAt(a_Position.x, a_Position.y, a_Position.z, [a_PoweringData](cHopperEntity & a_Hopper)
-			{
-				a_Hopper.SetLocked(a_PoweringData.PowerLevel != 0);
-				return false;
-			}
-		);
-		return {};
+		a_Chunk.DoWithHopperAt(a_Position, [a_PoweringData](cHopperEntity & a_Hopper)
+		{
+			a_Hopper.SetLocked(a_PoweringData.PowerLevel != 0);
+			return false;
+		});
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.cpp b/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.cpp
index 109ee4adc..2eb515604 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.cpp
+++ b/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.cpp
@@ -7,7 +7,6 @@
 
 #include "CommandBlockHandler.h"
 #include "DoorHandler.h"
-#include "RedstoneHandler.h"
 #include "RedstoneTorchHandler.h"
 #include "RedstoneWireHandler.h"
 #include "RedstoneRepeaterHandler.h"
@@ -31,9 +30,10 @@
 
 
 
+
 const cRedstoneHandler * cIncrementalRedstoneSimulator::GetComponentHandler(BLOCKTYPE a_BlockType)
 {
-	struct sComponents:
+	struct sComponents :
 		public std::array<std::unique_ptr<cRedstoneHandler>, 256>
 	{
 		sComponents()
@@ -128,76 +128,98 @@ std::unique_ptr<cRedstoneHandler> cIncrementalRedstoneSimulator::CreateComponent
 
 
 
-void cIncrementalRedstoneSimulator::Simulate(float a_dt)
+void cIncrementalRedstoneSimulator::SimulateChunk(std::chrono::milliseconds a_Dt, int a_ChunkX, int a_ChunkZ, cChunk * a_Chunk)
 {
-	for (auto & DelayInfo : m_Data.m_MechanismDelays)
+	auto & ChunkData = *static_cast<cIncrementalRedstoneSimulatorChunkData *>(a_Chunk->GetRedstoneSimulatorData());
+	for (auto & DelayInfo : ChunkData.m_MechanismDelays)
 	{
 		if ((--DelayInfo.second.first) == 0)
 		{
-			m_Data.GetActiveBlocks().emplace_back(DelayInfo.first);
+			ChunkData.WakeUp(DelayInfo.first);
 		}
 	}
 
 	// Build our work queue
-	cVector3iArray WorkQueue;
-	std::swap(WorkQueue, m_Data.GetActiveBlocks());
+	auto & WorkQueue = ChunkData.GetActiveBlocks();
 
 	// Process the work queue
 	while (!WorkQueue.empty())
 	{
 		// Grab the first element and remove it from the list
-		Vector3i CurrentLocation = WorkQueue.back();
-		WorkQueue.pop_back();
+		Vector3i CurrentLocation = WorkQueue.top();
+		WorkQueue.pop();
 
-		BLOCKTYPE CurrentBlock;
-		NIBBLETYPE CurrentMeta;
-		if (!m_World.GetBlockTypeMeta(CurrentLocation.x, CurrentLocation.y, CurrentLocation.z, CurrentBlock, CurrentMeta))
+		const auto NeighbourChunk = a_Chunk->GetRelNeighborChunkAdjustCoords(CurrentLocation);
+		if ((NeighbourChunk == nullptr) || !NeighbourChunk->IsValid())
 		{
-			continue;
+			return;
 		}
 
-		auto CurrentHandler = GetComponentHandler(CurrentBlock);
-		if (CurrentHandler == nullptr)  // Block at CurrentPosition doesn't have a corresponding redstone handler
-		{
-			// Clean up cached PowerData for CurrentPosition
-			GetChunkData()->ErasePowerData(CurrentLocation);
-			continue;
-		}
+		ProcessWorkItem(*NeighbourChunk, *a_Chunk, CurrentLocation);
+	}
+
+	for (const auto Position : ChunkData.AlwaysTickedPositions)
+	{
+		ChunkData.WakeUp(Position);
+	}
+}
+
 
-		cRedstoneHandler::PoweringData Power;
-		for (const auto & Location : CurrentHandler->GetValidSourcePositions(m_World, CurrentLocation, CurrentBlock, CurrentMeta))
-		{
-			if (!cChunk::IsValidHeight(Location.y))
-			{
-				continue;
-			}
 
-			BLOCKTYPE PotentialBlock;
-			NIBBLETYPE PotentialMeta;
-			if (!m_World.GetBlockTypeMeta(Location.x, Location.y, Location.z, PotentialBlock, PotentialMeta))
-			{
-				continue;
-			}
 
-			auto PotentialSourceHandler = GetComponentHandler(PotentialBlock);
-			if (PotentialSourceHandler == nullptr)
-			{
-				continue;
-			}
 
-			decltype(Power) PotentialPower(PotentialBlock, PotentialSourceHandler->GetPowerDeliveredToPosition(m_World, Location, PotentialBlock, PotentialMeta, CurrentLocation, CurrentBlock));
-			Power = std::max(Power, PotentialPower);
+void cIncrementalRedstoneSimulator::ProcessWorkItem(cChunk & Chunk, cChunk & TickingSource, const Vector3i Position)
+{
+	auto & ChunkData = *static_cast<cIncrementalRedstoneSimulatorChunkData *>(Chunk.GetRedstoneSimulatorData());
+
+	BLOCKTYPE CurrentBlock;
+	NIBBLETYPE CurrentMeta;
+	Chunk.GetBlockTypeMeta(Position, CurrentBlock, CurrentMeta);
+
+	auto CurrentHandler = GetComponentHandler(CurrentBlock);
+	if (CurrentHandler == nullptr)  // Block at CurrentPosition doesn't have a corresponding redstone handler
+	{
+		// Clean up cached PowerData for CurrentPosition
+		ChunkData.ErasePowerData(Position);
+		return;
+	}
+
+	PoweringData Power;
+	CurrentHandler->ForValidSourcePositions(Chunk, Position, CurrentBlock, CurrentMeta, [&Chunk, Position, CurrentBlock, &Power](Vector3i Location)
+	{
+		if (!cChunk::IsValidHeight(Location.y))
+		{
+			return;
 		}
 
-		// Inform the handler to update
-		cVector3iArray Updates = CurrentHandler->Update(m_World, CurrentLocation, CurrentBlock, CurrentMeta, Power);
-		WorkQueue.insert(WorkQueue.end(), Updates.begin(), Updates.end());
+		const auto NeighbourChunk = Chunk.GetRelNeighborChunkAdjustCoords(Location);
+		if ((NeighbourChunk == nullptr) || !NeighbourChunk->IsValid())
+		{
+			return;
+		}
 
-		if (IsAlwaysTicked(CurrentBlock))
+		BLOCKTYPE PotentialBlock;
+		NIBBLETYPE PotentialMeta;
+		NeighbourChunk->GetBlockTypeMeta(Location, PotentialBlock, PotentialMeta);
+
+		auto PotentialSourceHandler = GetComponentHandler(PotentialBlock);
+		if (PotentialSourceHandler == nullptr)
 		{
-			m_Data.GetActiveBlocks().emplace_back(CurrentLocation);
+			return;
 		}
-	}
+
+		const PoweringData PotentialPower(
+			PotentialBlock,
+			PotentialSourceHandler->GetPowerDeliveredToPosition(
+				*NeighbourChunk, Location, PotentialBlock, PotentialMeta,
+				cIncrementalRedstoneSimulatorChunkData::RebaseRelativePosition(Chunk, *NeighbourChunk, Position), CurrentBlock
+			)
+		);
+		Power = std::max(Power, PotentialPower);
+	});
+
+	// Inform the handler to update
+	CurrentHandler->Update(Chunk, TickingSource, Position, CurrentBlock, CurrentMeta, Power);
 }
 
 
@@ -206,27 +228,31 @@ void cIncrementalRedstoneSimulator::Simulate(float a_dt)
 
 void cIncrementalRedstoneSimulator::AddBlock(Vector3i a_Block, cChunk * a_Chunk)
 {
-	// Can't inspect block, so queue update anyway
-	if (a_Chunk == nullptr)
+	// Can't inspect block, ignore:
+	if ((a_Chunk == nullptr) || (!a_Chunk->IsValid()))
 	{
-		m_Data.WakeUp(a_Block);
 		return;
 	}
 
-	const auto RelPos = cChunkDef::AbsoluteToRelative(a_Block, a_Chunk->GetPos());
-	const auto CurBlock = a_Chunk->GetBlock(RelPos);
+	auto & ChunkData = *static_cast<cIncrementalRedstoneSimulatorChunkData *>(a_Chunk->GetRedstoneSimulatorData());
+	const auto Relative = cChunkDef::AbsoluteToRelative(a_Block, a_Chunk->GetPos());
+	const auto CurrentBlock = a_Chunk->GetBlock(Relative);
 
 	// Always update redstone devices
-	if (IsRedstone(CurBlock))
+	if (IsRedstone(CurrentBlock))
 	{
-		m_Data.WakeUp(a_Block);
+		if (IsAlwaysTicked(CurrentBlock))
+		{
+			ChunkData.AlwaysTickedPositions.emplace(Relative);
+		}
+		ChunkData.WakeUp(Relative);
 		return;
 	}
 
 	// Never update blocks without a handler
-	if (GetComponentHandler(CurBlock) == nullptr)
+	if (GetComponentHandler(CurrentBlock) == nullptr)
 	{
-		GetChunkData()->ErasePowerData(a_Block);
+		ChunkData.ErasePowerData(Relative);
 		return;
 	}
 
@@ -235,14 +261,14 @@ void cIncrementalRedstoneSimulator::AddBlock(Vector3i a_Block, cChunk * a_Chunk)
 	{
 		for (int y = -1; y < 2; ++y)
 		{
-			if (!cChunkDef::IsValidHeight(RelPos.y + y))
+			if (!cChunkDef::IsValidHeight(Relative.y + y))
 			{
 				continue;
 			}
 
 			for (int z = -1; z < 2; ++z)
 			{
-				auto CheckPos = RelPos + Vector3i{x, y, z};
+				auto CheckPos = Relative + Vector3i{x, y, z};
 				BLOCKTYPE Block;
 				NIBBLETYPE Meta;
 
@@ -252,7 +278,7 @@ void cIncrementalRedstoneSimulator::AddBlock(Vector3i a_Block, cChunk * a_Chunk)
 					IsRedstone(Block)
 				)
 				{
-					m_Data.WakeUp(a_Block);
+					ChunkData.WakeUp(Relative);
 					return;
 				}
 			}
diff --git a/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.h b/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.h
index 8213eddae..3523463bd 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/IncrementalRedstoneSimulator.h
@@ -2,26 +2,29 @@
 #pragma once
 
 #include "../RedstoneSimulator.h"
+#include "RedstoneHandler.h"
 #include "RedstoneSimulatorChunkData.h"
 
 
 
 
 
-class cIncrementalRedstoneSimulator:
+class cIncrementalRedstoneSimulator final :
 	public cRedstoneSimulator
 {
 	using Super = cRedstoneSimulator;
 
 public:
 
-	cIncrementalRedstoneSimulator(cWorld & a_World):
+	cIncrementalRedstoneSimulator(cWorld & a_World) :
 		Super(a_World)
 	{
 	}
 
-	virtual void Simulate(float a_dt) override;
-	virtual void SimulateChunk(std::chrono::milliseconds a_Dt, int a_ChunkX, int a_ChunkZ, cChunk * a_Chunk) override {}
+	virtual void Simulate(float Dt) override {};
+	virtual void SimulateChunk(std::chrono::milliseconds Dt, int ChunkX, int ChunkZ, cChunk * Chunk) override;
+
+	void ProcessWorkItem(cChunk & Chunk, cChunk & TickingSource, const Vector3i Position);
 
 	virtual cIncrementalRedstoneSimulatorChunkData * CreateChunkData() override
 	{
@@ -36,8 +39,7 @@ public:
 	virtual void AddBlock(Vector3i a_Block, cChunk * a_Chunk) override;
 
 	/** Returns if a block is a mechanism (something that accepts power and does something)
-	Used by torches to determine if they will power a block
-	*/
+	Used by torches to determine if they will power a block */
 	inline static bool IsMechanism(BLOCKTYPE Block)
 	{
 		switch (Block)
@@ -158,14 +160,9 @@ public:
 		}
 	}
 
-	cIncrementalRedstoneSimulatorChunkData * GetChunkData() { return &m_Data; }
-
 	static const cRedstoneHandler * GetComponentHandler(BLOCKTYPE a_BlockType);
 
 private:
 
 	static std::unique_ptr<cRedstoneHandler> CreateComponent(BLOCKTYPE a_BlockType);
-
-	// oh yea its crazy time
-	cIncrementalRedstoneSimulatorChunkData m_Data;
 } ;
diff --git a/src/Simulator/IncrementalRedstoneSimulator/NoteBlockHandler.h b/src/Simulator/IncrementalRedstoneSimulator/NoteBlockHandler.h
index f6dfc7c97..7d3ec2f30 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/NoteBlockHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/NoteBlockHandler.h
@@ -8,17 +8,13 @@
 
 
 
-class cNoteBlockHandler:
-	public cRedstoneHandler
+class cNoteBlockHandler: public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -27,41 +23,29 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating sparky the magical note block (%d %d %d) %i", a_Position.x, a_Position.y, a_Position.z, a_PoweringData.PowerLevel);
 
-		auto Previous = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
+		auto Previous = DataForChunk(a_Chunk).ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
 		if ((Previous.PowerLevel != 0) || (a_PoweringData.PowerLevel == 0))
 		{
 			// If we're already powered or received an update of no power, don't make a sound
-			return {};
+			return;
 		}
 
-		a_World.DoWithNoteBlockAt(a_Position.x, a_Position.y, a_Position.z, [](cNoteEntity & a_NoteBlock)
-			{
-				a_NoteBlock.MakeSound();
-				return false;
-			}
-		);
-
-		return {};
+		a_Chunk.DoWithNoteBlockAt(a_Position, [](cNoteEntity & a_NoteBlock)
+		{
+			a_NoteBlock.MakeSound();
+			return false;
+		});
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/ObserverHandler.h b/src/Simulator/IncrementalRedstoneSimulator/ObserverHandler.h
index b4af66aff..a3c055844 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/ObserverHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/ObserverHandler.h
@@ -8,7 +8,7 @@
 
 
 
-class cObserverHandler : public cRedstoneHandler
+class cObserverHandler final : public cRedstoneHandler
 {
 public:
 
@@ -17,24 +17,24 @@ public:
 		return (a_Meta & 0x8) == 0x8;
 	}
 
-	static bool ShouldPowerOn(cWorld & a_World, const Vector3i a_Position, NIBBLETYPE a_Meta, cIncrementalRedstoneSimulatorChunkData * a_Data)
+	static bool ShouldPowerOn(cChunk & Chunk, const Vector3i a_Position, NIBBLETYPE a_Meta, cIncrementalRedstoneSimulatorChunkData & a_Data)
 	{
 		BLOCKTYPE BlockType;
 		NIBBLETYPE BlockMeta;
-		if (!a_World.GetBlockTypeMeta(a_Position + cBlockObserverHandler::GetObservingFaceOffset(a_Meta), BlockType, BlockMeta))
+		if (!Chunk.UnboundedRelGetBlock(a_Position + cBlockObserverHandler::GetObservingFaceOffset(a_Meta), BlockType, BlockMeta))
 		{
 			return false;
 		}
 
 		// Cache the last seen block type and meta in the power data for this position
 		auto Observed = PoweringData(BlockType, BlockMeta);
-		auto Previous = a_Data->ExchangeUpdateOncePowerData(a_Position, Observed);
+		auto Previous = a_Data.ExchangeUpdateOncePowerData(a_Position, Observed);
 
 		// Determine if to signal an update based on the block previously observed changed
 		return (Previous.PoweringBlock != Observed.PoweringBlock) || (Previous.PowerLevel != Observed.PowerLevel);
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		if (IsOn(a_Meta) && (a_QueryPosition == (a_Position + cBlockObserverHandler::GetSignalOutputOffset(a_Meta))))
 		{
@@ -44,30 +44,25 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		return IsOn(a_BlockType) ? 15 : 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating Lenny the observer (%i %i %i)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto Data = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
-		auto DelayInfo = Data->GetMechanismDelayInfo(a_Position);
+		auto & Data = DataForChunk(a_Chunk);
+		auto DelayInfo = Data.GetMechanismDelayInfo(a_Position);
 
 		if (DelayInfo == nullptr)
 		{
-			if (!ShouldPowerOn(a_World, a_Position, a_Meta, Data))
+			if (!ShouldPowerOn(a_Chunk, a_Position, a_Meta, Data))
 			{
-				return {};
+				return;
 			}
 
 			// From rest, we've determined there was a block update
 			// Schedule power-on 1 tick in the future
-			Data->m_MechanismDelays[a_Position] = std::make_pair(1, true);
+			Data.m_MechanismDelays[a_Position] = std::make_pair(1, true);
 
-			return {};
+			return;
 		}
 
 		int DelayTicks;
@@ -76,31 +71,30 @@ public:
 
 		if (DelayTicks != 0)
 		{
-			return {};
+			return;
 		}
 
 		if (ShouldPowerOn)
 		{
 			// Remain on for 1 tick before resetting
 			*DelayInfo = std::make_pair(1, false);
-			a_World.SetBlockMeta(a_Position, a_Meta | 0x8);
+			a_Chunk.SetMeta(a_Position, a_Meta | 0x8);
 		}
 		else
 		{
 			// We've reset. Erase delay data in preparation for detecting further updates
-			Data->m_MechanismDelays.erase(a_Position);
-			a_World.SetBlockMeta(a_Position, a_Meta & ~0x8);
+			Data.m_MechanismDelays.erase(a_Position);
+			a_Chunk.SetMeta(a_Position, a_Meta & ~0x8);
 		}
 
-		return { a_Position + cBlockObserverHandler::GetSignalOutputOffset(a_Meta) };
+		UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position + cBlockObserverHandler::GetSignalOutputOffset(a_Meta));
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_BlockType);
-		return {};
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/PistonHandler.h b/src/Simulator/IncrementalRedstoneSimulator/PistonHandler.h
index 0929951d5..b3860a778 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/PistonHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/PistonHandler.h
@@ -8,16 +8,13 @@
 
 
 
-class cPistonHandler:
-	public cRedstoneHandler
+class cPistonHandler final: public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -26,52 +23,45 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating pisty the piston (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		bool ShouldBeExtended = (a_PoweringData.PowerLevel != 0);
+		const bool ShouldBeExtended = a_PoweringData.PowerLevel != 0;
 		if (ShouldBeExtended == cBlockPistonHandler::IsExtended(a_Meta))
 		{
-			return {};
+			return;
 		}
 
+		a_Position = cChunkDef::RelativeToAbsolute(a_Position, a_Chunk.GetPos());
+
 		if (ShouldBeExtended)
 		{
-			cBlockPistonHandler::ExtendPiston(a_Position, a_World);
+			cBlockPistonHandler::ExtendPiston(a_Position, *a_Chunk.GetWorld());
 		}
 		else
 		{
-			cBlockPistonHandler::RetractPiston(a_Position, a_World);
+			cBlockPistonHandler::RetractPiston(a_Position, *a_Chunk.GetWorld());
 		}
 
 		// It is necessary to delay after a signal to prevent an infinite loop (#3168)
-		// However, that is present as a side effect of the implementation of piston animation in Blocks\BlockPiston.cpp
-
-		return {};
+		// However, this delay is already present: as a side effect of the implementation of piston animation in Blocks\BlockPiston.cpp
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 
-		auto PositionsOffset = GetRelativeAdjacents();
-		auto Face = cBlockPistonHandler::MetaDataToDirection(a_Meta);
-		int OffsetX = 0, OffsetY = 0, OffsetZ = 0;
+		const auto Face = cBlockPistonHandler::MetaDataToDirection(a_Meta);
+		const auto FrontOffset = AddFaceDirection(Vector3i(), Face);
 
-		AddFaceDirection(OffsetX, OffsetY, OffsetZ, Face);
-		PositionsOffset.erase(std::remove(PositionsOffset.begin(), PositionsOffset.end(), Vector3i(OffsetX, OffsetY, OffsetZ)), PositionsOffset.end());
-
-		return GetAdjustedRelatives(a_Position, PositionsOffset);
+		for (const auto Offset : RelativeAdjacents)
+		{
+			if (Offset != FrontOffset)
+			{
+				Callback(a_Position + Offset);
+			}
+		}
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/PoweredRailHandler.h b/src/Simulator/IncrementalRedstoneSimulator/PoweredRailHandler.h
index d1d44a270..38fbf8d98 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/PoweredRailHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/PoweredRailHandler.h
@@ -7,11 +7,8 @@
 
 
 
-class cPoweredRailHandler:
-	public cRedstoneHandler
+class cPoweredRailHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
 	static Vector3i GetPoweredRailAdjacentXZCoordinateOffset(NIBBLETYPE a_Meta)  // Not in cBlockRailHandler since specific to powered rails
@@ -32,27 +29,20 @@ public:
 		}
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		UNUSED(a_QueryBlockType);
 
 		auto Offset = GetPoweredRailAdjacentXZCoordinateOffset(a_Meta);
 		if (((Offset + a_Position) == a_QueryPosition) || ((-Offset + a_Position) == a_QueryPosition))
 		{
-			auto Power = GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);
+			auto Power = DataForChunk(a_Chunk).GetCachedPowerData(a_Position).PowerLevel;
 			return (Power <= 7) ? 0 : --Power;
 		}
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->GetCachedPowerData(a_Position).PowerLevel;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTickingChunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating tracky the rail (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
@@ -66,33 +56,37 @@ public:
 					SetAllDirsAsPowered(a_RelBlockX, a_RelBlockY, a_RelBlockZ, a_MyType);
 				}
 				*/
-				return {};
+				return;
 			}
 			case E_BLOCK_ACTIVATOR_RAIL:
 			case E_BLOCK_POWERED_RAIL:
 			{
 				auto Offset = GetPoweredRailAdjacentXZCoordinateOffset(a_Meta);
-				if (a_PoweringData != static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, a_PoweringData))
+				if (a_PoweringData != DataForChunk(a_Chunk).ExchangeUpdateOncePowerData(a_Position, a_PoweringData))
 				{
-					a_World.SetBlockMeta(a_Position, (a_PoweringData.PowerLevel == 0) ? (a_Meta & 0x07) : (a_Meta | 0x08));
-					return cVector3iArray{ { Offset + a_Position }, { -Offset + a_Position } };
+					a_Chunk.SetMeta(a_Position, (a_PoweringData.PowerLevel == 0) ? (a_Meta & 0x07) : (a_Meta | 0x08));
+
+					UpdateAdjustedRelatives(a_Chunk, CurrentlyTickingChunk, a_Position + Offset);
+					UpdateAdjustedRelatives(a_Chunk, CurrentlyTickingChunk, a_Position + -Offset);
 				}
 
-				return {};
+				return;
 			}
 			default:
 			{
 				ASSERT(!"Unhandled type of rail in passed to rail handler!");
-				return {};
 			}
 		}
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
-		UNUSED(a_BlockType);
+		UNUSED(a_Chunk);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+
+		if ((a_BlockType == E_BLOCK_POWERED_RAIL) || (a_BlockType == E_BLOCK_ACTIVATOR_RAIL))
+		{
+			InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
+		}
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/PressurePlateHandler.h b/src/Simulator/IncrementalRedstoneSimulator/PressurePlateHandler.h
index 9f490b458..c2791e45c 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/PressurePlateHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/PressurePlateHandler.h
@@ -9,47 +9,42 @@
 
 
 
-class cPressurePlateHandler:
-	public cRedstoneHandler
+class cPressurePlateHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
 		UNUSED(a_QueryPosition);
 		UNUSED(a_QueryBlockType);
 
-		return static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->GetCachedPowerData(a_Position).PowerLevel;
+		return DataForChunk(a_Chunk).GetCachedPowerData(a_Position).PowerLevel;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	static unsigned char GetPowerLevel(cChunk & Chunk, const Vector3i Position, const BLOCKTYPE BlockType)
 	{
-		UNUSED(a_Meta);
-
-		int NumberOfEntities = 0;
+		unsigned NumberOfEntities = 0;
 		bool FoundPlayer = false;
-		a_World.ForEachEntityInBox(cBoundingBox(Vector3d(0.5, 0, 0.5) + a_Position, 0.5, 0.5), [&](cEntity & a_Entity)
+
+		Chunk.ForEachEntityInBox(cBoundingBox(Vector3d(0.5, 0, 0.5) + Position, 0.5, 0.5), [&](cEntity & Entity)
+		{
+			if (Entity.IsPlayer())
 			{
-				if (a_Entity.IsPlayer())
-				{
-					FoundPlayer = true;
-				}
-
-				if (a_Entity.IsPickup())
-				{
-					NumberOfEntities += static_cast<cPickup &>(a_Entity).GetItem().m_ItemCount;
-					return false;
-				}
-				NumberOfEntities++;
+				FoundPlayer = true;
+			}
+
+			if (Entity.IsPickup())
+			{
+				NumberOfEntities += static_cast<cPickup &>(Entity).GetItem().m_ItemCount;
 				return false;
 			}
-		);
+			NumberOfEntities++;
+			return false;
+		});
 
-		switch (a_BlockType)
+		switch (BlockType)
 		{
 			case E_BLOCK_STONE_PRESSURE_PLATE:
 			{
@@ -75,18 +70,22 @@ public:
 		}
 	}
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	static void UpdatePlate(cChunk & Chunk, cChunk & CurrentlyTicking, Vector3i Position)
 	{
-		UNUSED(a_PoweringData.PowerLevel);
-		// LOGD("Evaluating clicky the pressure plate (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
+		UpdateAdjustedRelatives(Chunk, CurrentlyTicking, Position, RelativeLaterals);
+		UpdateAdjustedRelatives(Chunk, CurrentlyTicking, Position + OffsetYM);
+	}
 
-		auto ChunkData = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	{
+		// LOGD("Evaluating clicky the pressure plate (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		const auto PreviousPower = ChunkData->GetCachedPowerData(a_Position);
-		auto Power = GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);  // Get the current power of the platey
+		auto & ChunkData = DataForChunk(a_Chunk);
 
-		const auto PlateUpdates = GetAdjustedRelatives(a_Position, StaticAppend(GetRelativeLaterals(), cVector3iArray{ OffsetYM() }));
-		auto DelayInfo = ChunkData->GetMechanismDelayInfo(a_Position);
+		const auto PreviousPower = ChunkData.GetCachedPowerData(a_Position);
+		const auto Absolute = cChunkDef::RelativeToAbsolute(a_Position, a_Chunk.GetPos());
+		const auto Power = GetPowerLevel(a_Chunk, Absolute, a_BlockType);  // Get the current power of the platey
+		const auto DelayInfo = ChunkData.GetMechanismDelayInfo(a_Position);
 
 		// Resting state?
 		if (DelayInfo == nullptr)
@@ -94,22 +93,21 @@ public:
 			if (Power == 0)
 			{
 				// Nothing happened, back to rest
-				return {};
+				return;
 			}
 
 			// From rest, a player stepped on us
 			// Schedule a minimum 0.5 second delay before even thinking about releasing
-			ChunkData->m_MechanismDelays[a_Position] = std::make_pair(5, true);
+			ChunkData.m_MechanismDelays[a_Position] = std::make_pair(5, true);
 
-			auto soundToPlay = GetClickOnSound(a_BlockType);
-			a_World.BroadcastSoundEffect(soundToPlay, a_Position, 0.5f, 0.6f);
+			a_Chunk.GetWorld()->BroadcastSoundEffect(GetClickOnSound(a_BlockType), Absolute, 0.5f, 0.6f);
 
 			// Update power
-			ChunkData->SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
+			ChunkData.SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
 
 			// Immediately depress plate
-			a_World.SetBlockMeta(a_Position, E_META_PRESSURE_PLATE_DEPRESSED);
-			return PlateUpdates;
+			a_Chunk.SetMeta(a_Position, E_META_PRESSURE_PLATE_DEPRESSED);
+			return UpdatePlate(a_Chunk, CurrentlyTicking, a_Position);
 		}
 
 		// Not a resting state
@@ -124,7 +122,7 @@ public:
 			// Nothing changes, if there is nothing on it anymore, because the state is locked.
 			if (Power == 0)
 			{
-				return {};
+				return;
 			}
 
 			// Yes. Are we waiting to release, and found that the player stepped on it again?
@@ -138,11 +136,11 @@ public:
 			if (Power != PreviousPower.PowerLevel)
 			{
 				// Yes. Update power
-				ChunkData->SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
-				return PlateUpdates;
+				ChunkData.SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
+				return UpdatePlate(a_Chunk, CurrentlyTicking, a_Position);
 			}
 
-			return {};
+			return;
 		}
 
 		// Not waiting for anything. Has the initial delay elapsed?
@@ -153,54 +151,51 @@ public:
 			{
 				// Yes. Go into subsequent release delay, for a further 0.5 seconds
 				*DelayInfo = std::make_pair(5, false);
-				return {};
+				return;
 			}
 
 			// Did the power level change and is still above zero?
 			if (Power != PreviousPower.PowerLevel)
 			{
 				// Yes. Update power
-				ChunkData->SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
-				return PlateUpdates;
+				ChunkData.SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
+				return UpdatePlate(a_Chunk, CurrentlyTicking, a_Position);
 			}
 
 			// Yes, but player's still on the plate, do nothing
-			return {};
+			return;
 		}
 
 		// Just got out of the subsequent release phase, reset everything and raise the plate
-		ChunkData->m_MechanismDelays.erase(a_Position);
+		ChunkData.m_MechanismDelays.erase(a_Position);
 
-		auto soundToPlay = GetClickOffSound(a_BlockType);
-		a_World.BroadcastSoundEffect(soundToPlay, a_Position, 0.5f, 0.5f);
-		ChunkData->SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
+		a_Chunk.GetWorld()->BroadcastSoundEffect(GetClickOffSound(a_BlockType), Absolute, 0.5f, 0.5f);
+		ChunkData.SetCachedPowerData(a_Position, PoweringData(a_BlockType, Power));
 
-		a_World.SetBlockMeta(a_Position, E_META_PRESSURE_PLATE_RAISED);
-		return PlateUpdates;
+		a_Chunk.SetMeta(a_Position, E_META_PRESSURE_PLATE_RAISED);
+		return UpdatePlate(a_Chunk, CurrentlyTicking, a_Position);
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return {};
+		UNUSED(Callback);
 	}
 
 private:
-	static AString GetClickOnSound(BLOCKTYPE a_BlockType)
+
+	static const char * GetClickOnSound(BLOCKTYPE a_BlockType)
 	{
 		// manage on-sound
 		switch (a_BlockType)
 		{
-			case E_BLOCK_STONE_PRESSURE_PLATE:
-				return "block.stone_pressureplate.click_on";
-			case E_BLOCK_WOODEN_PRESSURE_PLATE:
-				return "block.wood_pressureplate.click_on";
+			case E_BLOCK_STONE_PRESSURE_PLATE: return "block.stone_pressureplate.click_on";
+			case E_BLOCK_WOODEN_PRESSURE_PLATE: return "block.wood_pressureplate.click_on";
 			case E_BLOCK_HEAVY_WEIGHTED_PRESSURE_PLATE:
-			case E_BLOCK_LIGHT_WEIGHTED_PRESSURE_PLATE:
-				return "block.metal_pressureplate.click_on";
+			case E_BLOCK_LIGHT_WEIGHTED_PRESSURE_PLATE: return "block.metal_pressureplate.click_on";
 			default:
 			{
 				ASSERT(!"No on sound for this one!");
@@ -209,18 +204,15 @@ private:
 		}
 	}
 
-	static AString GetClickOffSound(BLOCKTYPE a_BlockType)
+	static const char * GetClickOffSound(BLOCKTYPE a_BlockType)
 	{
 		// manage off-sound
 		switch (a_BlockType)
 		{
-			case E_BLOCK_STONE_PRESSURE_PLATE:
-				return "block.stone_pressureplate.click_off";
-			case E_BLOCK_WOODEN_PRESSURE_PLATE:
-				return "block.wood_pressureplate.click_off";
+			case E_BLOCK_STONE_PRESSURE_PLATE: return "block.stone_pressureplate.click_off";
+			case E_BLOCK_WOODEN_PRESSURE_PLATE: return "block.wood_pressureplate.click_off";
 			case E_BLOCK_HEAVY_WEIGHTED_PRESSURE_PLATE:
-			case E_BLOCK_LIGHT_WEIGHTED_PRESSURE_PLATE:
-				return "block.metal_pressureplate.click_off";
+			case E_BLOCK_LIGHT_WEIGHTED_PRESSURE_PLATE: return "block.metal_pressureplate.click_off";
 			default:
 			{
 				ASSERT(!"No off sound for this one!");
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneBlockHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneBlockHandler.h
index 98d373002..150723944 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneBlockHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneBlockHandler.h
@@ -7,16 +7,13 @@
 
 
 
-class cRedstoneBlockHandler:
-	public cRedstoneHandler
+class cRedstoneBlockHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -24,27 +21,17 @@ public:
 		return cIncrementalRedstoneSimulator::IsMechanism(a_QueryBlockType) ? 15 : 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 15;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating crimson the redstone block (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return {};
+		UNUSED(Callback);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneComparatorHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneComparatorHandler.h
index 3c5dae98f..5827c806b 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneComparatorHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneComparatorHandler.h
@@ -8,14 +8,11 @@
 
 
 
-class cRedstoneComparatorHandler:
-	public cRedstoneHandler
+class cRedstoneComparatorHandler : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	unsigned char GetFrontPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, unsigned char a_HighestSidePowerLevel, unsigned char a_HighestRearPowerLevel) const
+	static unsigned char GetFrontPowerLevel(NIBBLETYPE a_Meta, unsigned char a_HighestSidePowerLevel, unsigned char a_HighestRearPowerLevel)
 	{
 		if (cBlockComparatorHandler::IsInSubtractionMode(a_Meta))
 		{
@@ -29,107 +26,120 @@ public:
 		}
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		UNUSED(a_QueryPosition);
 		UNUSED(a_QueryBlockType);
-		auto ChunkData = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
 
 		return (
 			(cBlockComparatorHandler::GetFrontCoordinate(a_Position, a_Meta & 0x3) == a_QueryPosition) ?
-			ChunkData->GetCachedPowerData(a_Position).PowerLevel : 0
+			DataForChunk(a_Chunk).GetCachedPowerData(a_Position).PowerLevel : 0
 		);
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	static unsigned char GetPowerLevel(cChunk & a_Chunk, Vector3i Position, BLOCKTYPE BlockType, NIBBLETYPE Meta)
 	{
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-
 		UInt8 SignalStrength = 0;
-		auto RearCoordinate = cBlockComparatorHandler::GetRearCoordinate(a_Position, a_Meta & 0x3);
-		a_World.DoWithBlockEntityAt(RearCoordinate.x, RearCoordinate.y, RearCoordinate.z, [&](cBlockEntity & a_BlockEntity)
+		auto RearCoordinate = cBlockComparatorHandler::GetRearCoordinate(Position, Meta & 0x3);
+
+		auto RearChunk = a_Chunk.GetRelNeighborChunkAdjustCoords(RearCoordinate);
+		if ((RearChunk == nullptr) || !RearChunk->IsValid())
+		{
+			return SignalStrength;
+		}
+
+		RearChunk->DoWithBlockEntityAt(RearCoordinate, [&](cBlockEntity & a_BlockEntity)
+		{
+			// Skip BlockEntities that don't have slots
+			auto BlockEntityWithItems = dynamic_cast<cBlockEntityWithItems *>(&a_BlockEntity);
+			if (BlockEntityWithItems == nullptr)
 			{
-				// Skip BlockEntities that don't have slots
-				auto BlockEntityWithItems = dynamic_cast<cBlockEntityWithItems *>(&a_BlockEntity);
-				if (BlockEntityWithItems == nullptr)
-				{
-					return false;
-				}
-
-				auto & Contents = BlockEntityWithItems->GetContents();
-				float Fullness = 0;  // Is a floating-point type to allow later calculation to produce a non-truncated value
-
-				for (int Slot = 0; Slot != Contents.GetNumSlots(); ++Slot)
-				{
-					Fullness += static_cast<float>(Contents.GetSlot(Slot).m_ItemCount) / Contents.GetSlot(Slot).GetMaxStackSize();
-				}
-
-				SignalStrength = (Fullness < 0.001 /* container empty? */) ? 0 : static_cast<UInt8>(1 + (Fullness / Contents.GetNumSlots()) * 14);
 				return false;
 			}
-		);
-		auto RearPower = SignalStrength;
-		auto RearType = a_World.GetBlock(RearCoordinate);
+
+			// TODO: handle double chests
+
+			auto & Contents = BlockEntityWithItems->GetContents();
+			float Fullness = 0;  // Is a floating-point type to allow later calculation to produce a non-truncated value
+
+			for (int Slot = 0; Slot != Contents.GetNumSlots(); ++Slot)
+			{
+				Fullness += static_cast<float>(Contents.GetSlot(Slot).m_ItemCount) / Contents.GetSlot(Slot).GetMaxStackSize();
+			}
+
+			SignalStrength = (Fullness < 0.001 /* container empty? */) ? 0 : static_cast<UInt8>(1 + (Fullness / Contents.GetNumSlots()) * 14);
+			return false;
+		});
+
+		BLOCKTYPE RearType;
+		NIBBLETYPE RearMeta;
+		RearChunk->GetBlockTypeMeta(RearCoordinate, RearType, RearMeta);
 
 		auto PotentialSourceHandler = cIncrementalRedstoneSimulator::GetComponentHandler(RearType);
-		if (PotentialSourceHandler != nullptr)
+		if (PotentialSourceHandler == nullptr)
 		{
-			NIBBLETYPE RearMeta = a_World.GetBlockMeta(RearCoordinate);
-			RearPower = std::max(SignalStrength, PotentialSourceHandler->GetPowerDeliveredToPosition(a_World, RearCoordinate, RearType, RearMeta, a_Position, a_BlockType));
+			return SignalStrength;
 		}
 
-		return RearPower;
+		return std::max(
+			SignalStrength,
+			PotentialSourceHandler->GetPowerDeliveredToPosition(
+				*RearChunk, RearCoordinate, RearType, RearMeta,
+				cIncrementalRedstoneSimulatorChunkData::RebaseRelativePosition(a_Chunk, *RearChunk, Position), BlockType
+			)
+		);
 	}
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// Note that a_PoweringData here contains the maximum * side * power level, as specified by GetValidSourcePositions
 		// LOGD("Evaluating ALU the comparator (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
-		auto Data = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
-		auto DelayInfo = Data->GetMechanismDelayInfo(a_Position);
+
+		auto & Data = DataForChunk(a_Chunk);
+		auto DelayInfo = Data.GetMechanismDelayInfo(a_Position);
 
 		// Delay is used here to prevent an infinite loop (#3168)
 		if (DelayInfo == nullptr)
 		{
-			auto RearPower = GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);
-			auto FrontPower = GetFrontPowerLevel(a_World, a_Position, a_BlockType, a_Meta, a_PoweringData.PowerLevel, RearPower);
-			auto PreviousFrontPower = Data->ExchangeUpdateOncePowerData(a_Position, PoweringData(a_PoweringData.PoweringBlock, FrontPower));
+			const auto RearPower = GetPowerLevel(a_Chunk, a_Position, a_BlockType, a_Meta);
+			const auto FrontPower = GetFrontPowerLevel(a_Meta, a_PoweringData.PowerLevel, RearPower);
+			const auto PreviousFrontPower = Data.GetCachedPowerData(a_Position);
+			const bool ShouldUpdate = (FrontPower != PreviousFrontPower.PowerLevel);  // "Business logic" (:P) - determined by side and rear power levels
 
-			bool ShouldBeOn = (RearPower > 0);  // Provide visual indication by examining * rear * power level
-			bool ShouldUpdate = (FrontPower != PreviousFrontPower.PowerLevel);  // "Business logic" (:P) - determine by examining *side* power levels
-
-			if (ShouldUpdate || (ShouldBeOn != cBlockComparatorHandler::IsOn(a_Meta)))
+			if (ShouldUpdate)
 			{
-				Data->m_MechanismDelays[a_Position] = std::make_pair(1, ShouldBeOn);
+				Data.m_MechanismDelays[a_Position] = std::make_pair(1, bool());
 			}
 		}
 		else
 		{
 			int DelayTicks;
-			bool ShouldPowerOn;
-			std::tie(DelayTicks, ShouldPowerOn) = *DelayInfo;
+			std::tie(DelayTicks, std::ignore) = *DelayInfo;
 
 			if (DelayTicks == 0)
 			{
-				a_World.SetBlockMeta(a_Position, ShouldPowerOn ? (a_Meta | 0x8) : (a_Meta & 0x7));
-				Data->m_MechanismDelays.erase(a_Position);
-
-				// Assume that an update (to front power) is needed.
-				// Note: potential inconsistencies will arise as power data is updated before-delay due to limitations of the power data caching functionality (only stores one bool)
-				// This means that other mechanisms like wires may get our new power data before our delay has finished
-				// This also means that we have to manually update ourselves to be aware of any changes that happened in the previous redstone tick
-				return StaticAppend(GetAdjustedRelatives(a_Position, GetRelativeLaterals()), cVector3iArray{ a_Position });
+				const auto RearPower = GetPowerLevel(a_Chunk, a_Position, a_BlockType, a_Meta);
+				const auto FrontPower = GetFrontPowerLevel(a_Meta, a_PoweringData.PowerLevel, RearPower);
+				const auto NewMeta = (FrontPower > 0) ? (a_Meta | 0x8) : (a_Meta & 0x7);
+
+				// Don't care about the previous power level so return value ignored
+				Data.ExchangeUpdateOncePowerData(a_Position, PoweringData(a_PoweringData.PoweringBlock, FrontPower));
+
+				a_Chunk.SetMeta(a_Position, NewMeta);
+				Data.m_MechanismDelays.erase(a_Position);
+
+				// Assume that an update (to front power) is needed:
+				UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, cBlockComparatorHandler::GetFrontCoordinate(a_Position, a_Meta & 0x3));
 			}
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
-		return cVector3iArray {cBlockComparatorHandler::GetSideCoordinate(a_Position, a_Meta & 0x3, false), cBlockComparatorHandler::GetSideCoordinate(a_Position, a_Meta & 0x3, true)};
+
+		Callback(cBlockComparatorHandler::GetSideCoordinate(a_Position, a_Meta & 0x3, false));
+		Callback(cBlockComparatorHandler::GetSideCoordinate(a_Position, a_Meta & 0x3, true));
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneHandler.h
index 2d0ac97b9..fec38b14d 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneHandler.h
@@ -1,7 +1,8 @@
 
 #pragma once
 
-#include "../../World.h"
+#include "../../Chunk.h"
+#include "RedstoneSimulatorChunkData.h"
 
 
 
@@ -14,50 +15,11 @@ public:
 	cRedstoneHandler() = default;
 	DISALLOW_COPY_AND_ASSIGN(cRedstoneHandler);
 
-	struct PoweringData
-	{
-	public:
-		PoweringData(BLOCKTYPE a_PoweringBlock, unsigned char a_PowerLevel) :
-			PoweringBlock(a_PoweringBlock),
-			PowerLevel(a_PowerLevel)
-		{
-		}
-
-		PoweringData(void) :
-			PoweringBlock(E_BLOCK_AIR),
-			PowerLevel(0)
-		{
-		}
-
-		BLOCKTYPE PoweringBlock;
-		unsigned char PowerLevel;
-
-		inline friend bool operator < (const PoweringData & a_Lhs, const PoweringData & a_Rhs)
-		{
-			return (
-				(a_Lhs.PowerLevel < a_Rhs.PowerLevel) ||
-				(
-					(a_Lhs.PowerLevel == a_Rhs.PowerLevel) &&
-					((a_Lhs.PoweringBlock == E_BLOCK_REDSTONE_WIRE) && (a_Rhs.PoweringBlock != E_BLOCK_REDSTONE_WIRE))
-				)
-			);
-		}
-
-		inline friend bool operator == (const PoweringData & a_Lhs, const PoweringData & a_Rhs)
-		{
-			return (a_Lhs.PowerLevel == a_Rhs.PowerLevel);
-		}
-
-		inline friend bool operator != (const PoweringData & a_Lhs, const PoweringData & a_Rhs)
-		{
-			return !operator ==(a_Lhs, a_Rhs);
-		}
-	};
+	using SourceCallback = cFunctionRef<void(Vector3i)>;
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const = 0;
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const = 0;
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const = 0;
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const = 0;
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const = 0;
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const = 0;
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const = 0;
 
 	// Force a virtual destructor
 	virtual ~cRedstoneHandler() {}
@@ -72,15 +34,9 @@ protected:
 		return ToReturn;
 	}
 
-	inline static Vector3i OffsetYP()
-	{
-		return Vector3i(0, 1, 0);
-	}
+	inline static Vector3i OffsetYP{ 0, 1, 0 };
 
-	inline static Vector3i OffsetYM()
-	{
-		return Vector3i(0, -1, 0);
-	}
+	inline static Vector3i OffsetYM{ 0, -1, 0 };
 
 	static cVector3iArray GetAdjustedRelatives(Vector3i a_Position, cVector3iArray a_Relatives)
 	{
@@ -91,31 +47,68 @@ protected:
 		return a_Relatives;
 	}
 
-	inline static cVector3iArray GetRelativeAdjacents()
+	inline static cIncrementalRedstoneSimulatorChunkData & DataForChunk(cChunk & a_Chunk)
+	{
+		return *static_cast<cIncrementalRedstoneSimulatorChunkData *>(a_Chunk.GetRedstoneSimulatorData());
+	}
+
+	template <typename... ArrayTypes>
+	static void UpdateAdjustedRelatives(cChunk & From, cChunk & To, const Vector3i Position)
 	{
-		return
+		DataForChunk(To).WakeUp(cIncrementalRedstoneSimulatorChunkData::RebaseRelativePosition(From, To, Position));
+	}
+
+	template <typename ArrayType, typename... ArrayTypes>
+	static void UpdateAdjustedRelatives(cChunk & From, cChunk & To, const Vector3i Position, const ArrayType & Relative, const ArrayTypes &... Relatives)
+	{
+		for (const auto Offset : Relative)
+		{
+			DataForChunk(To).GetActiveBlocks().push(cIncrementalRedstoneSimulatorChunkData::RebaseRelativePosition(From, To, Position + Offset));
+		}
+
+		UpdateAdjustedRelatives(From, To, Position, Relatives...);
+	}
+
+	template <typename ArrayType, typename... ArrayTypes>
+	static void InvokeForAdjustedRelatives(SourceCallback Callback, Vector3i Position, const ArrayType & Relative, const ArrayTypes &... Relatives)
+	{
+		for (const auto Offset : Relative)
 		{
-			{
-				{ 1, 0, 0 },
-				{ -1, 0, 0 },
-				{ 0, 1, 0 },
-				{ 0, -1, 0 },
-				{ 0, 0, 1 },
-				{ 0, 0, -1 },
-			}
-		};
+			Callback(Position + Offset);
+		}
+
+		InvokeForAdjustedRelatives(Callback, Position, Relatives...);
 	}
 
-	inline static cVector3iArray GetRelativeLaterals()
+	inline static std::array<Vector3i, 6> RelativeAdjacents
+	{
+		{
+			{ 1, 0, 0 },
+			{ -1, 0, 0 },
+			{ 0, 1, 0 },
+			{ 0, -1, 0 },
+			{ 0, 0, 1 },
+			{ 0, 0, -1 },
+		}
+	};
+
+	inline static std::array<Vector3i, 4> RelativeLaterals
 	{
-		return
 		{
-			{
-				{ 1, 0, 0 },
-				{ -1, 0, 0 },
-				{ 0, 0, 1 },
-				{ 0, 0, -1 },
-			}
-		};
+			{ 1, 0, 0 },
+			{ -1, 0, 0 },
+			{ 0, 0, 1 },
+			{ 0, 0, -1 },
+		}
+	};
+
+private:
+
+	static void UpdateAdjustedRelatives(cVector3iArray &, Vector3i)
+	{
+	}
+
+	static void InvokeForAdjustedRelatives(SourceCallback, Vector3i)
+	{
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneLampHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneLampHandler.h
index 7c967af9c..85aa1d743 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneLampHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneLampHandler.h
@@ -5,7 +5,7 @@
 
 
 
-class cRedstoneLampHandler : public cRedstoneHandler
+class cRedstoneLampHandler final : public cRedstoneHandler
 {
 public:
 
@@ -14,17 +14,12 @@ public:
 		return (a_BlockType == E_BLOCK_REDSTONE_LAMP_ON);
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating lamp (%i %i %i)", a_Position.x, a_Position.y, a_Position.z);
 
@@ -32,25 +27,23 @@ public:
 		{
 			if (!IsOn(a_BlockType))
 			{
-				a_World.SetBlock(a_Position.x, a_Position.y, a_Position.z, E_BLOCK_REDSTONE_LAMP_ON, 0);
+				a_Chunk.FastSetBlock(a_Position, E_BLOCK_REDSTONE_LAMP_ON, 0);
 			}
 		}
 		else
 		{
 			if (IsOn(a_BlockType))
 			{
-				a_World.SetBlock(a_Position.x, a_Position.y, a_Position.z, E_BLOCK_REDSTONE_LAMP_OFF, 0);
+				a_Chunk.FastSetBlock(a_Position, E_BLOCK_REDSTONE_LAMP_OFF, 0);
 			}
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Meta);
 		UNUSED(a_BlockType);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneRepeaterHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneRepeaterHandler.h
index 0cd65be53..4174ac930 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneRepeaterHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneRepeaterHandler.h
@@ -15,37 +15,27 @@ class cRedstoneRepeaterHandler:
 
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		return (
-			(a_QueryPosition == (a_Position + cBlockRedstoneRepeaterHandler::GetFrontCoordinateOffset(a_Meta))) ?
-			GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta) : 0
-		);
+		return ((a_QueryPosition == (a_Position + cBlockRedstoneRepeaterHandler::GetFrontCoordinateOffset(a_Meta))) && IsOn(a_BlockType)) ? 15 : 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_Meta);
-		return IsOn(a_BlockType) ? 15 : 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating loopy the repeater (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
-		auto Data = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
-		auto DelayInfo = Data->GetMechanismDelayInfo(a_Position);
+
+		auto & Data = DataForChunk(a_Chunk);
+		const auto DelayInfo = Data.GetMechanismDelayInfo(a_Position);
 
 		// If the repeater is locked by another, ignore and forget all power changes:
-		if (IsLocked(a_World, a_Position, a_Meta))
+		if (IsLocked(a_Chunk, a_Position, a_Meta))
 		{
 			if (DelayInfo != nullptr)
 			{
-				Data->m_MechanismDelays.erase(a_Position);
+				Data.m_MechanismDelays.erase(a_Position);
 			}
 
-			return {};
+			return;
 		}
 
 		if (DelayInfo == nullptr)
@@ -53,7 +43,7 @@ public:
 			bool ShouldBeOn = (a_PoweringData.PowerLevel != 0);
 			if (ShouldBeOn != IsOn(a_BlockType))
 			{
-				Data->m_MechanismDelays[a_Position] = std::make_pair((((a_Meta & 0xC) >> 0x2) + 1), ShouldBeOn);
+				Data.m_MechanismDelays[a_Position] = std::make_pair((((a_Meta & 0xC) >> 0x2) + 1), ShouldBeOn);
 			}
 		}
 		else
@@ -64,18 +54,23 @@ public:
 
 			if (DelayTicks == 0)
 			{
-				a_World.SetBlock(a_Position.x, a_Position.y, a_Position.z, ShouldPowerOn ? E_BLOCK_REDSTONE_REPEATER_ON : E_BLOCK_REDSTONE_REPEATER_OFF, a_Meta);
-				Data->m_MechanismDelays.erase(a_Position);
-				return cVector3iArray{ cBlockRedstoneRepeaterHandler::GetFrontCoordinateOffset(a_Meta) + a_Position };
+				const auto NewType = ShouldPowerOn ? E_BLOCK_REDSTONE_REPEATER_ON : E_BLOCK_REDSTONE_REPEATER_OFF;
+				a_Chunk.FastSetBlock(a_Position, NewType, a_Meta);
+				Data.m_MechanismDelays.erase(a_Position);
+
+				// While sleeping, we ignore any power changes and apply our saved ShouldBeOn when sleep expires
+				// Now, we need to recalculate to be aware of any new changes that may e.g. cause a new output change
+				// FastSetBlock doesn't wake simulators, so manually update ourselves:
+				Update(a_Chunk, CurrentlyTicking, a_Position, NewType, a_Meta, a_PoweringData);
+
+				UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position + cBlockRedstoneRepeaterHandler::GetFrontCoordinateOffset(a_Meta));
 			}
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		return { cBlockRedstoneRepeaterHandler::GetRearCoordinateOffset(a_Meta) + a_Position };
+		Callback(cBlockRedstoneRepeaterHandler::GetRearCoordinateOffset(a_Meta) + a_Position);
 	}
 
 private:
@@ -87,12 +82,12 @@ private:
 
 	/** Returns a pair with first element indicating if the block at the given position is an activated repeater.
 	If it is activated, the second element is the repeater metadata. */
-	static std::pair<bool, NIBBLETYPE> IsOnRepeater(cWorld & a_World, const Vector3i a_Position)
+	static std::pair<bool, NIBBLETYPE> IsOnRepeater(cChunk & Chunk, const Vector3i a_Position)
 	{
 		BLOCKTYPE Type;
 		NIBBLETYPE Meta;
 
-		if (!a_World.GetBlockTypeMeta(a_Position, Type, Meta))
+		if (!Chunk.UnboundedRelGetBlock(a_Position, Type, Meta))
 		{
 			return std::make_pair(false, 0);
 		}
@@ -103,20 +98,20 @@ private:
 	/** Determine if a repeater is locked.
 	A locked repeater is one with another powered repeater facing them, to their immediate left or right sides.
 	"Left" is relative to the direction the repeater output faces, naturally. */
-	inline static bool IsLocked(cWorld & a_World, const Vector3i a_Position, const NIBBLETYPE a_Meta)
+	inline static bool IsLocked(cChunk & Chunk, const Vector3i a_Position, const NIBBLETYPE a_Meta)
 	{
 		// The left hand side offset. Will be negated to get the rhs offset
 		const auto LhsOffset = cBlockRedstoneRepeaterHandler::GetLeftCoordinateOffset(a_Meta);
 
 		// Test the block to the left of us
-		const auto Lhs = IsOnRepeater(a_World, LhsOffset + a_Position);
+		const auto Lhs = IsOnRepeater(Chunk, LhsOffset + a_Position);
 		if (Lhs.first && DoesLhsLockMe(Lhs.second, a_Meta))
 		{
 			return true;
 		}
 
 		// Test the right side, flipping the argument order to DoesLhsLockMe
-		const auto Rhs = IsOnRepeater(a_World, -LhsOffset + a_Position);
+		const auto Rhs = IsOnRepeater(Chunk, -LhsOffset + a_Position);
 		return Rhs.first && DoesLhsLockMe(a_Meta, Rhs.second);
 	}
 
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneSimulatorChunkData.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneSimulatorChunkData.h
index a842770a5..71d43d00e 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneSimulatorChunkData.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneSimulatorChunkData.h
@@ -1,73 +1,132 @@
 
 #pragma once
 
-#include "RedstoneHandler.h"
+#include <stack>
+
 #include "../RedstoneSimulator.h"
 
 
 
 
 
-class cIncrementalRedstoneSimulatorChunkData : public cRedstoneSimulatorChunkData
+struct PoweringData
 {
+public:
+	PoweringData(BLOCKTYPE a_PoweringBlock, unsigned char a_PowerLevel) :
+		PoweringBlock(a_PoweringBlock),
+		PowerLevel(a_PowerLevel)
+	{
+	}
+
+	PoweringData(void) :
+		PoweringBlock(E_BLOCK_AIR),
+		PowerLevel(0)
+	{
+	}
 
+	BLOCKTYPE PoweringBlock;
+	unsigned char PowerLevel;
+
+	inline friend bool operator < (const PoweringData & Lhs, const PoweringData & Rhs)
+	{
+		return (
+			(Lhs.PowerLevel < Rhs.PowerLevel) ||
+			(
+				(Lhs.PowerLevel == Rhs.PowerLevel) &&
+				((Lhs.PoweringBlock == E_BLOCK_REDSTONE_WIRE) && (Rhs.PoweringBlock != E_BLOCK_REDSTONE_WIRE))
+			)
+		);
+	}
+
+	inline friend bool operator == (const PoweringData & Lhs, const PoweringData & Rhs)
+	{
+		return (Lhs.PowerLevel == Rhs.PowerLevel);
+	}
+
+	inline friend bool operator != (const PoweringData & Lhs, const PoweringData & Rhs)
+	{
+		return !operator ==(Lhs, Rhs);
+	}
+};
+
+
+
+
+
+class cIncrementalRedstoneSimulatorChunkData : public cRedstoneSimulatorChunkData
+{
 public:
+
 	void WakeUp(const Vector3i & a_Position)
 	{
-		m_ActiveBlocks.push_back(a_Position);
+		ActiveBlocks.push(a_Position);
 	}
 
-	cVector3iArray & GetActiveBlocks()
+	auto & GetActiveBlocks()
 	{
-		return m_ActiveBlocks;
+		return ActiveBlocks;
 	}
 
-	const cRedstoneHandler::PoweringData GetCachedPowerData(const Vector3i & a_Position) const
+	const PoweringData GetCachedPowerData(const Vector3i Position) const
 	{
-		auto Result = m_CachedPowerLevels.find(a_Position);
-		return (Result == m_CachedPowerLevels.end()) ? cRedstoneHandler::PoweringData() : Result->second;
+		auto Result = CachedPowerLevels.find(Position);
+		return (Result == CachedPowerLevels.end()) ? PoweringData() : Result->second;
 	}
 
-	void SetCachedPowerData(const Vector3i & a_Position, cRedstoneHandler::PoweringData a_PoweringData)
+	void SetCachedPowerData(const Vector3i Position, PoweringData PoweringData)
 	{
-		m_CachedPowerLevels[a_Position] = a_PoweringData;
+		CachedPowerLevels[Position] = PoweringData;
 	}
 
-	std::pair<int, bool> * GetMechanismDelayInfo(const Vector3i & a_Position)
+	std::pair<int, bool> * GetMechanismDelayInfo(const Vector3i Position)
 	{
-		auto Result = m_MechanismDelays.find(a_Position);
+		auto Result = m_MechanismDelays.find(Position);
 		return (Result == m_MechanismDelays.end()) ? nullptr : &Result->second;
 	}
 
-	/** Erase cached PowerData for position */
-	void ErasePowerData(const Vector3i & a_Position)
+	/** Erase all cached redstone data for position. */
+	void ErasePowerData(const Vector3i Position)
 	{
-		m_CachedPowerLevels.erase(a_Position);
-		m_MechanismDelays.erase(a_Position);
+		CachedPowerLevels.erase(Position);
+		m_MechanismDelays.erase(Position);
+		AlwaysTickedPositions.erase(Position);
 	}
 
-	cRedstoneHandler::PoweringData ExchangeUpdateOncePowerData(const Vector3i & a_Position, cRedstoneHandler::PoweringData a_PoweringData)
+	PoweringData ExchangeUpdateOncePowerData(const Vector3i & a_Position, PoweringData a_PoweringData)
 	{
-		auto Result = m_CachedPowerLevels.find(a_Position);
-		if (Result == m_CachedPowerLevels.end())
+		auto Result = CachedPowerLevels.find(a_Position);
+		if (Result == CachedPowerLevels.end())
 		{
-			m_CachedPowerLevels[a_Position] = a_PoweringData;
-			return cRedstoneHandler::PoweringData();
+			CachedPowerLevels[a_Position] = a_PoweringData;
+			return PoweringData();
 		}
 		std::swap(Result->second, a_PoweringData);
 		return a_PoweringData;
 	}
 
+	/** Adjust From-relative coordinates into To-relative coordinates. */
+	inline static Vector3i RebaseRelativePosition(cChunk & From, cChunk & To, const Vector3i Position)
+	{
+		return
+		{
+			Position.x + (From.GetPosX() - To.GetPosX()) * cChunkDef::Width,
+			Position.y,
+			Position.z + (From.GetPosZ() - To.GetPosZ()) * cChunkDef::Width
+		};
+	}
+
+	std::unordered_set<Vector3i, VectorHasher<int>> AlwaysTickedPositions;
+
 	/** Structure storing position of mechanism + it's delay ticks (countdown) & if to power on */
 	std::unordered_map<Vector3i, std::pair<int, bool>, VectorHasher<int>> m_MechanismDelays;
 
 private:
 
-	cVector3iArray m_ActiveBlocks;
+	std::stack<Vector3i, std::vector<Vector3i>> ActiveBlocks;
 
 	// TODO: map<Vector3i, int> -> Position of torch + it's heat level
 
-	std::unordered_map<Vector3i, cRedstoneHandler::PoweringData, VectorHasher<int>> m_CachedPowerLevels;
+	std::unordered_map<Vector3i, PoweringData, VectorHasher<int>> CachedPowerLevels;
 
 	friend class cRedstoneHandlerFactory;
 
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneToggleHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneToggleHandler.h
index c56b09c7b..bf9c639b1 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneToggleHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneToggleHandler.h
@@ -9,11 +9,8 @@
 
 
 
-class cRedstoneToggleHandler:
-	public cRedstoneHandler
+class cRedstoneToggleHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
 	inline static Vector3i GetPositionAttachedTo(Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta)
@@ -65,21 +62,18 @@ public:
 		}
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		UNUSED(a_QueryBlockType);
 		if ((GetPositionAttachedTo(a_Position, a_BlockType, a_Meta) == a_QueryPosition) || cIncrementalRedstoneSimulator::IsMechanism(a_QueryBlockType))
 		{
-			return GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);
+			return GetPowerLevel(a_BlockType, a_Meta);
 		}
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	static unsigned char GetPowerLevel(BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta)
 	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-
 		switch (a_BlockType)
 		{
 			case E_BLOCK_LEVER: return cBlockLeverHandler::IsLeverOn(a_Meta) ? 15 : 0;
@@ -93,18 +87,17 @@ public:
 		}
 	}
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating templatio<> the lever/button (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return {};
+		UNUSED(Callback);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneTorchHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneTorchHandler.h
index 16f060939..c935e1f1b 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneTorchHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneTorchHandler.h
@@ -7,7 +7,7 @@
 
 
 
-class cRedstoneTorchHandler : public cRedstoneHandler
+class cRedstoneTorchHandler final : public cRedstoneHandler
 {
 public:
 
@@ -33,12 +33,12 @@ public:
 		}
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		if (
 			IsOn(a_BlockType) &&
 			(a_QueryPosition != (a_Position + GetOffsetAttachedTo(a_Position, a_Meta))) &&
-			(cIncrementalRedstoneSimulator::IsMechanism(a_QueryBlockType) || (cBlockInfo::FullyOccupiesVoxel(a_QueryBlockType) && (a_QueryPosition == (a_Position + OffsetYP()))))
+			(cIncrementalRedstoneSimulator::IsMechanism(a_QueryBlockType) || (cBlockInfo::FullyOccupiesVoxel(a_QueryBlockType) && (a_QueryPosition == (a_Position + OffsetYP))))
 		)
 		{
 			return 15;
@@ -46,24 +46,19 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		return IsOn(a_BlockType) ? 15 : 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating torchy the redstone torch (%i %i %i)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto Data = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
-		auto DelayInfo = Data->GetMechanismDelayInfo(a_Position);
+		auto & Data = DataForChunk(a_Chunk);
+		auto DelayInfo = Data.GetMechanismDelayInfo(a_Position);
 
 		if (DelayInfo == nullptr)
 		{
 			bool ShouldBeOn = (a_PoweringData.PowerLevel == 0);
 			if (ShouldBeOn != IsOn(a_BlockType))
 			{
-				Data->m_MechanismDelays[a_Position] = std::make_pair(1, ShouldBeOn);
+				Data.m_MechanismDelays[a_Position] = std::make_pair(1, ShouldBeOn);
 			}
 		}
 		else
@@ -72,24 +67,28 @@ public:
 			bool ShouldPowerOn;
 			std::tie(DelayTicks, ShouldPowerOn) = *DelayInfo;
 
-			if (DelayTicks == 0)
+			if (DelayTicks != 0)
 			{
-				a_World.SetBlock(a_Position.x, a_Position.y, a_Position.z, ShouldPowerOn ? E_BLOCK_REDSTONE_TORCH_ON : E_BLOCK_REDSTONE_TORCH_OFF, a_Meta);
-				Data->m_MechanismDelays.erase(a_Position);
+				return;
+			}
 
-				cVector3iArray RelativePositions = GetRelativeAdjacents();
-				RelativePositions.erase(std::remove(RelativePositions.begin(), RelativePositions.end(), GetOffsetAttachedTo(a_Position, a_Meta)), RelativePositions.end());
-				return GetAdjustedRelatives(a_Position, RelativePositions);
+			a_Chunk.SetBlock(a_Position, ShouldPowerOn ? E_BLOCK_REDSTONE_TORCH_ON : E_BLOCK_REDSTONE_TORCH_OFF, a_Meta);
+			Data.m_MechanismDelays.erase(a_Position);
+
+			for (const auto Adjacent : RelativeAdjacents)
+			{
+				if (Adjacent != GetOffsetAttachedTo(a_Position, a_Meta))
+				{
+					UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position + Adjacent);
+				}
 			}
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
-		return { (a_Position + GetOffsetAttachedTo(a_Position, a_Meta)) };
+		Callback(a_Position + GetOffsetAttachedTo(a_Position, a_Meta));
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/RedstoneWireHandler.h b/src/Simulator/IncrementalRedstoneSimulator/RedstoneWireHandler.h
index e7666f560..3a782d1d3 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/RedstoneWireHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/RedstoneWireHandler.h
@@ -7,11 +7,8 @@
 
 
 
-class cRedstoneWireHandler:
-	public cRedstoneHandler
+class cRedstoneWireHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
 	inline static bool IsDirectlyConnectingMechanism(BLOCKTYPE a_Block, NIBBLETYPE a_BlockMeta, const Vector3i a_Offset)
@@ -40,133 +37,170 @@ public:
 		}
 	}
 
-	cVector3iArray GetTerracingConnectionOffsets(cWorld & a_World, const Vector3i a_Position) const
+	template <class OffsetCallback>
+	static bool ForTerracingConnectionOffsets(cChunk & a_Chunk, const Vector3i a_Position, OffsetCallback Callback)
 	{
-		auto RelativePositions = GetRelativeLaterals();
-		const auto YPTerraceBlock = a_World.GetBlock(a_Position + OffsetYP());
+		const auto YPTerraceBlock = a_Chunk.GetBlock(a_Position + OffsetYP);
 		const bool IsYPTerracingBlocked = cBlockInfo::IsSolid(YPTerraceBlock) && !cBlockInfo::IsTransparent(YPTerraceBlock);
 
-		for (const auto & Adjacent : GetRelativeLaterals())
+		for (const auto Adjacent : RelativeLaterals)
 		{
+			// All laterals are counted as terracing, duh
+			if (Callback(Adjacent))
+			{
+				return true;
+			}
+
 			if (
+				BLOCKTYPE YPBlock;
+
 				// A block above us blocks all YP terracing, so the check is static in the loop
 				!IsYPTerracingBlocked &&
-				(a_World.GetBlock(a_Position + Adjacent + OffsetYP()) == E_BLOCK_REDSTONE_WIRE)
+				a_Chunk.UnboundedRelGetBlockType(a_Position + Adjacent + OffsetYP, YPBlock) &&
+				(YPBlock == E_BLOCK_REDSTONE_WIRE)
 			)
 			{
-				RelativePositions.emplace_back(Adjacent + OffsetYP());
+				if (Callback(Adjacent + OffsetYP))
+				{
+					return true;
+				}
 			}
 
-			const auto YMTerraceBlock = a_World.GetBlock(a_Position + Adjacent);
 			if (
+				BLOCKTYPE YMTerraceBlock, YMDiagonalBlock;
+
 				// IsYMTerracingBlocked (i.e. check block above lower terracing position, a.k.a. just the plain adjacent)
+				a_Chunk.UnboundedRelGetBlockType(a_Position + Adjacent, YMTerraceBlock) &&
 				(!cBlockInfo::IsSolid(YMTerraceBlock) || cBlockInfo::IsTransparent(YMTerraceBlock)) &&
-				(a_World.GetBlock(a_Position + Adjacent + OffsetYM()) == E_BLOCK_REDSTONE_WIRE)
+
+				a_Chunk.UnboundedRelGetBlockType(a_Position + Adjacent + OffsetYM, YMDiagonalBlock) &&
+				(YMDiagonalBlock == E_BLOCK_REDSTONE_WIRE)
 			)
 			{
-				RelativePositions.emplace_back(Adjacent + OffsetYM());
+				if (Callback(Adjacent + OffsetYM))
+				{
+					return true;
+				}
 			}
 		}
 
-		return RelativePositions;
+		return false;
 	}
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		if (a_QueryPosition == (a_Position + OffsetYP()))
+		if (a_QueryPosition == (a_Position + OffsetYP))
 		{
 			// Wires do not power things above them
 			return 0;
 		}
 
-		if (a_QueryBlockType != E_BLOCK_REDSTONE_WIRE)
+		if (a_QueryBlockType == E_BLOCK_REDSTONE_WIRE)
 		{
 			// For mechanisms, wire of power one will still power them
-			a_Meta++;
+			// But for wire-to-wire connections, power level decreases by 1
+			return (a_Meta != 0) ? --a_Meta : a_Meta;
 		}
 
 		// Wires always deliver power to the block underneath, and any directly connecting mechanisms
 		if (
-			(a_QueryPosition != (a_Position + OffsetYM())) &&
-			!IsDirectlyConnectingMechanism(a_QueryBlockType, a_World.GetBlockMeta(a_QueryPosition), a_QueryPosition - a_Position)
+			NIBBLETYPE QueryMeta;
+
+			(a_QueryPosition == (a_Position + OffsetYM)) ||
+			(a_Chunk.UnboundedRelGetBlockMeta(a_QueryPosition, QueryMeta) && IsDirectlyConnectingMechanism(a_QueryBlockType, QueryMeta, a_QueryPosition - a_Position))
 		)
 		{
-			/*
-			Okay, we do not directly connect to the wire.
-			If there are no DC mechanisms at all, the wire powers all laterals. Great, we fall out the loop.
-			If there is one DC mechanism, the wire "goes straight" along the axis of the wire and mechanism.
-			The only possible way for us to be powered is for us to be on the opposite end, with the wire pointing towards us.
-			If there is more than one DC, no non-DCs are powered.
-			*/
-
-			Vector3i PotentialOffset;
-			bool FoundOneBorderingMechanism = false;
-
-			for (const auto & Offset : GetTerracingConnectionOffsets(a_World, a_Position))
+			return a_Meta;
+		}
+
+		/*
+		Okay, we do not directly connect to the wire.
+		If there are no DC mechanisms at all, the wire powers all laterals. Great, we fall out the loop.
+		If there is one DC mechanism, the wire "goes straight" along the axis of the wire and mechanism.
+		The only possible way for us to be powered is for us to be on the opposite end, with the wire pointing towards us.
+		If there is more than one DC, no non-DCs are powered.
+		*/
+
+		Vector3i PotentialOffset;
+		bool FoundOneBorderingMechanism = false;
+
+		if (
+			ForTerracingConnectionOffsets(a_Chunk, a_Position, [&a_Chunk, a_Position, &FoundOneBorderingMechanism, &PotentialOffset](const Vector3i Offset)
 			{
 				BLOCKTYPE Block;
 				NIBBLETYPE Meta;
 
 				if (
-					!a_World.GetBlockTypeMeta(Offset + a_Position, Block, Meta) ||
+					!a_Chunk.UnboundedRelGetBlock(Offset + a_Position, Block, Meta) ||
 					!IsDirectlyConnectingMechanism(Block, Meta, Offset)
 				)
 				{
-					continue;
+					return false;
 				}
 
 				if (FoundOneBorderingMechanism)
 				{
 					// Case 3
-					return 0;
+					return true;
 				}
 
 				// Potential case 2
 				FoundOneBorderingMechanism = true;
 				PotentialOffset = { -Offset.x, 0, -Offset.z };
-			}
 
-			if (FoundOneBorderingMechanism && (a_QueryPosition != (a_Position + PotentialOffset)))
-			{
-				// Case 2 fail
-				return 0;
-			}
+				return false;
+			})
+		)
+		{
+			// Case 3
+			return 0;
+		}
 
-			// Case 1
-			// Case 2 success
+		if (FoundOneBorderingMechanism && (a_QueryPosition != (a_Position + PotentialOffset)))
+		{
+			// Case 2 fail
+			return 0;
 		}
 
-		return (a_Meta != 0) ? --a_Meta : a_Meta;
-	}
+		// Case 1
+		// Case 2 success
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
 		return a_Meta;
 	}
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
-		UNUSED(a_BlockType);
 		// LOGD("Evaluating dusty the wire (%d %d %d) %i", a_Position.x, a_Position.y, a_Position.z, a_PoweringData.PowerLevel);
 
 		if (a_Meta != a_PoweringData.PowerLevel)
 		{
-			a_World.SetBlockMeta(a_Position, a_PoweringData.PowerLevel);
-			return GetAdjustedRelatives(a_Position, StaticAppend(StaticAppend(GetRelativeLaterals(), GetTerracingConnectionOffsets(a_World, a_Position)), cVector3iArray{ OffsetYM() }));
-		}
+			a_Chunk.SetMeta(a_Position, a_PoweringData.PowerLevel);
+
+			// Notify block below us to update:
+			UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position + OffsetYM);
 
-		return {};
+			// Notify all terracing positions:
+			ForTerracingConnectionOffsets(a_Chunk, a_Position, [&a_Chunk, &CurrentlyTicking, a_Position](const Vector3i Offset)
+			{
+				UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position + Offset);
+				return false;
+			});
+		}
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
 
-		return GetAdjustedRelatives(a_Position, StaticAppend(GetRelativeAdjacents(), GetTerracingConnectionOffsets(a_World, a_Position)));
+		Callback(a_Position + OffsetYP);
+		Callback(a_Position + OffsetYM);
+
+		ForTerracingConnectionOffsets(a_Chunk, a_Position, [&Callback, a_Position](const Vector3i Offset)
+		{
+			Callback(a_Position + Offset);
+			return false;
+		});
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/SmallGateHandler.h b/src/Simulator/IncrementalRedstoneSimulator/SmallGateHandler.h
index 48238f4eb..0bf2faacd 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/SmallGateHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/SmallGateHandler.h
@@ -7,16 +7,13 @@
 
 
 
-class cSmallGateHandler:
-	public cRedstoneHandler
+class cSmallGateHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -25,32 +22,24 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating gateydory the fence gate/trapdoor (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
-		auto Data = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData();
-		if (a_PoweringData != Data->ExchangeUpdateOncePowerData(a_Position, a_PoweringData))
+
+		const bool ShouldBeOpen = a_PoweringData.PowerLevel != 0;
+		const bool IsOpen = (a_Meta & 0x4) == 0x4;
+
+		if (ShouldBeOpen != IsOpen)
 		{
-			a_World.SetBlockMeta(a_Position, (a_PoweringData.PowerLevel > 0) ? (a_Meta | 0x4) : (a_Meta & ~0x04));
+			a_Chunk.SetMeta(a_Position, ShouldBeOpen ? (a_Meta | 0x4) : (a_Meta & ~0x04));
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/SolidBlockHandler.h b/src/Simulator/IncrementalRedstoneSimulator/SolidBlockHandler.h
index 5b6bafaa3..abf8dc63b 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/SolidBlockHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/SolidBlockHandler.h
@@ -14,41 +14,34 @@ class cSolidBlockHandler:
 
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		// TODO: wire isn't linked powered only if the source was a wire, not just because it is a wire
+		const auto SolidBlock = DataForChunk(a_Chunk).GetCachedPowerData(a_Position);
 		return (
 			!cIncrementalRedstoneSimulator::IsRedstone(a_QueryBlockType) ||
 			(
 				(a_QueryBlockType == E_BLOCK_REDSTONE_WIRE) &&
-				(static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->GetCachedPowerData(a_Position).PoweringBlock == E_BLOCK_REDSTONE_WIRE)
+				(SolidBlock.PoweringBlock == E_BLOCK_REDSTONE_WIRE)
 			)
-		) ? 0 : GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);
+		) ? 0 : SolidBlock.PowerLevel;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		return static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->GetCachedPowerData(a_Position).PowerLevel;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
 		// LOGD("Evaluating blocky the generic block (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto PreviousPower = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
+		auto PreviousPower = DataForChunk(a_Chunk).ExchangeUpdateOncePowerData(a_Position, a_PoweringData);
 		if ((a_PoweringData != PreviousPower) || (a_PoweringData.PoweringBlock != PreviousPower.PoweringBlock))
 		{
-			return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+			UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position, RelativeAdjacents);
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
 
@@ -64,6 +57,6 @@ public:
 			}
 		}
 		*/
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/TNTHandler.h b/src/Simulator/IncrementalRedstoneSimulator/TNTHandler.h
index 1ded2a733..4b048e5c2 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/TNTHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/TNTHandler.h
@@ -7,16 +7,13 @@
 
 
 
-class cTNTHandler:
-	public cRedstoneHandler
+class cTNTHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
@@ -25,31 +22,21 @@ public:
 		return 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
-	{
-		UNUSED(a_World);
-		UNUSED(a_Position);
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-		return 0;
-	}
-
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk &, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating explodinator the trinitrotoluene (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 		if (a_PoweringData.PowerLevel != 0)
 		{
-			a_World.SetBlock(a_Position.x, a_Position.y, a_Position.z, E_BLOCK_AIR, 0);
-			a_World.SpawnPrimedTNT(Vector3d(a_Position) + Vector3d(0.5, 0.5, 0.5));  // 80 ticks to boom
+			a_Chunk.SetBlock(a_Position, E_BLOCK_AIR, 0);
+			a_Chunk.GetWorld()->SpawnPrimedTNT(Vector3d(0.5, 0.5, 0.5) + cChunkDef::RelativeToAbsolute(a_Position, a_Chunk.GetPos()));  // 80 ticks to boom
 		}
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-		return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+		InvokeForAdjustedRelatives(Callback, a_Position, RelativeAdjacents);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/TrappedChestHandler.h b/src/Simulator/IncrementalRedstoneSimulator/TrappedChestHandler.h
index e8483a73a..707c239e9 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/TrappedChestHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/TrappedChestHandler.h
@@ -15,54 +15,51 @@ class cTrappedChestHandler:
 
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
 		UNUSED(a_QueryPosition);
 		UNUSED(a_QueryBlockType);
 
-		return static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->GetCachedPowerData(a_Position).PowerLevel;
+		return DataForChunk(a_Chunk).GetCachedPowerData(a_Position).PowerLevel;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	static unsigned char GetPowerLevel(cChunk & a_Chunk, Vector3i a_Position)
 	{
-		UNUSED(a_BlockType);
-		UNUSED(a_Meta);
-
 		int NumberOfPlayers = 0;
-		VERIFY(!a_World.DoWithChestAt(a_Position.x, a_Position.y, a_Position.z, [&](cChestEntity & a_Chest)
+		VERIFY(
+			!a_Chunk.DoWithChestAt(a_Position, [&](cChestEntity & a_Chest)
 			{
 				ASSERT(a_Chest.GetBlockType() == E_BLOCK_TRAPPED_CHEST);
 				NumberOfPlayers = a_Chest.GetNumberOfPlayers();
 				return true;
-			}
-		));
+			})
+		);
+
 		return static_cast<unsigned char>(std::min(NumberOfPlayers, 15));
 	}
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating tricky the trapped chest (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto Power = GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);
-		auto PreviousPower = static_cast<cIncrementalRedstoneSimulator *>(a_World.GetRedstoneSimulator())->GetChunkData()->ExchangeUpdateOncePowerData(a_Position, PoweringData(a_BlockType, Power));
+		const auto Power = GetPowerLevel(a_Chunk, a_Position);
+		const auto PreviousPower = DataForChunk(a_Chunk).ExchangeUpdateOncePowerData(a_Position, PoweringData(a_BlockType, Power));
 
 		if (Power != PreviousPower.PowerLevel)
 		{
-			return GetAdjustedRelatives(a_Position, StaticAppend(GetRelativeLaterals(), cVector3iArray{ OffsetYM() }));
+			UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, OffsetYM);
+			UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position, RelativeLaterals);
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_Position);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
-
-		return {};
+		UNUSED(Callback);
 	}
 };
diff --git a/src/Simulator/IncrementalRedstoneSimulator/TripwireHookHandler.h b/src/Simulator/IncrementalRedstoneSimulator/TripwireHookHandler.h
index 6a857cd7c..7c00c4e2f 100644
--- a/src/Simulator/IncrementalRedstoneSimulator/TripwireHookHandler.h
+++ b/src/Simulator/IncrementalRedstoneSimulator/TripwireHookHandler.h
@@ -8,43 +8,53 @@
 
 
 
-class cTripwireHookHandler:
-	public cRedstoneHandler
+class cTripwireHookHandler final : public cRedstoneHandler
 {
-	using Super = cRedstoneHandler;
-
 public:
 
-	virtual unsigned char GetPowerDeliveredToPosition(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
+	virtual unsigned char GetPowerDeliveredToPosition(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, Vector3i a_QueryPosition, BLOCKTYPE a_QueryBlockType) const override
 	{
+		UNUSED(a_BlockType);
 		UNUSED(a_QueryBlockType);
 		UNUSED(a_QueryPosition);
 
-		return (GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta) == 15) ? 15 : 0;
+		return (GetPowerLevel(a_Chunk, a_Position, a_Meta) == 15) ? 15 : 0;
 	}
 
-	virtual unsigned char GetPowerLevel(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	static unsigned char GetPowerLevel(cChunk & a_Chunk, Vector3i a_Position, NIBBLETYPE a_Meta)
 	{
-		UNUSED(a_BlockType);
-
 		bool FoundActivated = false;
-		auto Position = a_Position;
-		eBlockFace FaceToGoTowards = cBlockTripwireHookHandler::MetadataToDirection(a_Meta);
+		const auto FaceToGoTowards = cBlockTripwireHookHandler::MetadataToDirection(a_Meta);
 
 		for (int i = 0; i < 40; ++i)  // Tripwires can be connected up to 40 blocks
 		{
 			BLOCKTYPE Type;
 			NIBBLETYPE Meta;
 
-			AddFaceDirection(Position.x, Position.y, Position.z, FaceToGoTowards);
-			a_World.GetBlockTypeMeta(Position.x, Position.y, Position.z, Type, Meta);
+			a_Position = AddFaceDirection(a_Position, FaceToGoTowards);
+			if (!a_Chunk.UnboundedRelGetBlock(a_Position, Type, Meta))
+			{
+				return 0;
+			}
 
 			if (Type == E_BLOCK_TRIPWIRE)
 			{
-				if (!a_World.ForEachEntityInBox(cBoundingBox(Vector3d(0.5, 0, 0.5) + Position, 0.5, 0.5), [](cEntity &) { return true; }))
+				if (FoundActivated)
+				{
+					continue;
+				}
+
+				if (
+					!a_Chunk.ForEachEntityInBox(
+						cBoundingBox(Vector3d(0.5, 0, 0.5) + cChunkDef::RelativeToAbsolute(a_Position, a_Chunk.GetPos()), 0.5, 0.5),
+						[](cEntity &) { return true; }
+					)
+				)
 				{
 					FoundActivated = true;
 				}
+
+				continue;
 			}
 			else if (Type == E_BLOCK_TRIPWIRE_HOOK)
 			{
@@ -53,27 +63,20 @@ public:
 					// Other hook facing in opposite direction - circuit completed!
 					return FoundActivated ? 15 : 1;
 				}
-				else
-				{
-					// Tripwire hook not connected at all
-					return 0;
-				}
-			}
-			else
-			{
-				// Tripwire hook not connected at all
-				return 0;
 			}
+
+			// Tripwire hook not connected at all
+			return 0;
 		}
 
 		return 0;
 	}
 
-	virtual cVector3iArray Update(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
+	virtual void Update(cChunk & a_Chunk, cChunk & CurrentlyTicking, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, PoweringData a_PoweringData) const override
 	{
 		// LOGD("Evaluating hooky the tripwire hook (%d %d %d)", a_Position.x, a_Position.y, a_Position.z);
 
-		auto Power = GetPowerLevel(a_World, a_Position, a_BlockType, a_Meta);
+		const auto Power = GetPowerLevel(a_Chunk, a_Position, a_Meta);
 		NIBBLETYPE Meta;
 		if (Power == 0)
 		{
@@ -91,25 +94,22 @@ public:
 		}
 		else
 		{
-			ASSERT(!"Unexpected tripwire hook power level!");
-			return {};
+			UNREACHABLE("Unexpected tripwire hook power level!");
 		}
 
 		if (Meta != a_Meta)
 		{
-			a_World.SetBlockMeta(a_Position, Meta);
-			return GetAdjustedRelatives(a_Position, GetRelativeAdjacents());
+			a_Chunk.SetMeta(a_Position, Meta);
+			UpdateAdjustedRelatives(a_Chunk, CurrentlyTicking, a_Position, RelativeAdjacents);
 		}
-
-		return {};
 	}
 
-	virtual cVector3iArray GetValidSourcePositions(cWorld & a_World, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta) const override
+	virtual void ForValidSourcePositions(cChunk & a_Chunk, Vector3i a_Position, BLOCKTYPE a_BlockType, NIBBLETYPE a_Meta, SourceCallback Callback) const override
 	{
-		UNUSED(a_World);
+		UNUSED(a_Chunk);
 		UNUSED(a_BlockType);
 		UNUSED(a_Meta);
 		UNUSED(a_Position);
-		return {};
+		UNUSED(Callback);
 	}
 };
diff --git a/src/Simulator/NoopRedstoneSimulator.h b/src/Simulator/NoopRedstoneSimulator.h
index 4959882fa..91436ce7e 100644
--- a/src/Simulator/NoopRedstoneSimulator.h
+++ b/src/Simulator/NoopRedstoneSimulator.h
@@ -7,7 +7,7 @@
 
 
 
-class cRedstoneNoopSimulator:
+class cRedstoneNoopSimulator final :
 	public cRedstoneSimulator
 {
 	using Super = cRedstoneSimulator;