diff --git a/src/chunk.zig b/src/chunk.zig
index e76d51c12..6054ba433 100644
--- a/src/chunk.zig
+++ b/src/chunk.zig
@@ -202,6 +202,9 @@ pub const Chunk = struct {
 	}
 
 	pub fn deinit(self: *Chunk) void {
+		if(self.wasChanged) {
+			self.save(main.server.world.?);
+		}
 		self.data.deinit();
 		memoryPoolMutex.lock();
 		memoryPool.destroy(@alignCast(self));
@@ -278,10 +281,13 @@ pub const Chunk = struct {
 		return self.data.getValue(index);
 	}
 
-	pub fn updateFromLowerResolution(self: *Chunk, other: *const Chunk) void {
+	pub fn updateFromLowerResolution(self: *Chunk, other: *Chunk) void {
 		const xOffset = if(other.pos.wx != self.pos.wx) chunkSize/2 else 0; // Offsets of the lower resolution chunk in this chunk.
 		const yOffset = if(other.pos.wy != self.pos.wy) chunkSize/2 else 0;
 		const zOffset = if(other.pos.wz != self.pos.wz) chunkSize/2 else 0;
+		self.mutex.lock();
+		defer self.mutex.unlock();
+		main.utils.assertLocked(&other.mutex);
 		
 		var x: u31 = 0;
 		while(x < chunkSize/2): (x += 1) {
@@ -302,7 +308,10 @@ pub const Chunk = struct {
 								const index = getIndex(x*2 + dx, y*2 + dy, z*2 + dz);
 								const i = dx*4 + dz*2 + dy;
 								octantBlocks[i] = other.data.getValue(index);
-								if(octantBlocks[i].typ == 0) continue; // I don't care about air blocks.
+								if(octantBlocks[i].typ == 0) {
+									neighborCount[i] = 0;
+									continue; // I don't care about air blocks.
+								}
 								
 								var count: u31 = 0;
 								for(Neighbors.iterable) |n| {
diff --git a/src/game.zig b/src/game.zig
index 9393f428e..0d53bbd54 100644
--- a/src/game.zig
+++ b/src/game.zig
@@ -126,18 +126,18 @@ pub const World = struct {
 
 	pub fn deinit(self: *World) void {
 		// TODO: Close all world related guis.
+		main.threadPool.clear();
 		self.conn.deinit();
 		self.itemDrops.deinit();
 		self.blockPalette.deinit();
 		Player.inventory__SEND_CHANGES_TO_SERVER.deinit(main.globalAllocator);
 		self.manager.deinit();
-		assets.unloadAssets();
 		main.server.stop();
-		main.threadPool.clear();
 		if(main.server.thread) |serverThread| {
 			serverThread.join();
 			main.server.thread = null;
 		}
+		assets.unloadAssets();
 	}
 
 	pub fn finishHandshake(self: *World, json: JsonElement) !void {
diff --git a/src/main.zig b/src/main.zig
index 2319ca7d9..b24a0334a 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -440,9 +440,6 @@ pub fn main() void {
 		}
 	}
 
-	// Make sure that threadPool is done before freeing any data
-	threadPool.clear();
-
 	if(game.world) |world| {
 		world.deinit();
 		game.world = null;
diff --git a/src/network.zig b/src/network.zig
index ae0ade4f1..5c0a5736e 100644
--- a/src/network.zig
+++ b/src/network.zig
@@ -817,12 +817,10 @@ pub const Protocols = struct {
 			const y = std.mem.readInt(i32, data[4..8], .big);
 			const z = std.mem.readInt(i32, data[8..12], .big);
 			const newBlock = Block.fromInt(std.mem.readInt(u32, data[12..16], .big));
-			if(conn.user != null) {
-				// TODO: Store changes in batches to reduce cost of singe block updates.
+			if(conn.user != null) { // TODO: Send update event to other players.
 				const mask = ~@as(i32, chunk.chunkMask);
 				const ch = main.server.world.?.getOrGenerateChunk(.{.wx = x & mask, .wy = y & mask, .wz = z & mask, .voxelSize = 1});
 				ch.updateBlockAndSetChanged(x & chunk.chunkMask, y & chunk.chunkMask, z & chunk.chunkMask, newBlock);
-				ch.save(main.server.world.?);
 			} else {
 				renderer.mesh_storage.updateBlock(x, y, z, newBlock);
 			}
diff --git a/src/server/world.zig b/src/server/world.zig
index 5405feebd..1a04ee6e0 100644
--- a/src/server/world.zig
+++ b/src/server/world.zig
@@ -158,8 +158,9 @@ const ChunkManager = struct {
 	}
 
 	pub fn deinit(self: ChunkManager) void {
-		// TODO: Save chunks
-		chunkCache.clear();
+		for(0..main.settings.highestLOD) |_| {
+			chunkCache.clear();
+		}
 		server.terrain.deinit();
 		main.assets.unloadAssets();
 		self.terrainGenerationProfile.deinit();
@@ -180,7 +181,7 @@ const ChunkManager = struct {
 		const ch = getOrGenerateChunk(pos);
 		if(source) |_source| {
 			main.network.Protocols.chunkTransmission.sendChunk(_source.conn, ch);
-		} else { // TODO: This feature was temporarily removed to keep compatibility with the zig version.
+		} else {
 			server.mutex.lock();
 			defer server.mutex.unlock();
 			for(server.users.items) |user| {
@@ -220,7 +221,6 @@ const ChunkManager = struct {
 
 	fn chunkDeinitFunctionForCache(ch: *Chunk) void {
 		ch.deinit();
-		// TODO: Store chunk.
 	}
 	/// Generates a normal chunk at a given location, or if possible gets it from the cache.
 	pub fn getOrGenerateChunk(pos: ChunkPosition) *Chunk { // TODO: This is not thread safe! The chunk could get removed from the cache while in use. Reference counting should probably be used here.