diff --git a/res/textures/blocks/blue_lamp.png b/res/textures/blocks/blue_lamp.png
new file mode 100644
index 00000000..ffb01964
Binary files /dev/null and b/res/textures/blocks/blue_lamp.png differ
diff --git a/res/textures/blocks/green_lamp.png b/res/textures/blocks/green_lamp.png
new file mode 100644
index 00000000..cea33901
Binary files /dev/null and b/res/textures/blocks/green_lamp.png differ
diff --git a/res/textures/blocks/red_lamp.png b/res/textures/blocks/red_lamp.png
new file mode 100644
index 00000000..15d02238
Binary files /dev/null and b/res/textures/blocks/red_lamp.png differ
diff --git a/src/definitions.cpp b/src/definitions.cpp
index 748b8812..6378d523 100644
--- a/src/definitions.cpp
+++ b/src/definitions.cpp
@@ -89,6 +89,18 @@ void setup_definitions(ContentBuilder* builder) {
 
 	block = new Block("base:rust", "rust");
 	builder->add(block);
+
+	block = new Block("base:red_lamp", "red_lamp");
+	block->emission[0] = 15;
+	builder->add(block);
+
+	block = new Block("base:green_lamp", "green_lamp");
+	block->emission[1] = 15;
+	builder->add(block);
+
+	block = new Block("base:blue_lamp", "blue_lamp");
+	block->emission[2] = 15;
+	builder->add(block);
 }
 
 void setup_bindings() {
diff --git a/src/files/WorldFiles.cpp b/src/files/WorldFiles.cpp
index 92ea421f..85664a6c 100644
--- a/src/files/WorldFiles.cpp
+++ b/src/files/WorldFiles.cpp
@@ -4,9 +4,11 @@
 #include "rle.h"
 #include "binary_io.h"
 #include "../window/Camera.h"
+#include "../content/Content.h"
 #include "../objects/Player.h"
 #include "../physics/Hitbox.h"
 #include "../voxels/voxel.h"
+#include "../voxels/Block.h"
 #include "../voxels/Chunk.h"
 #include "../typedefs.h"
 #include "../maths/voxmaths.h"
@@ -102,8 +104,12 @@ void WorldFiles::put(Chunk* chunk){
 	region.compressedSizes[chunk_index] = compressedSize;
 }
 
+path WorldFiles::getRegionsFolder() const {
+	return directory/path("regions");
+}
+
 path WorldFiles::getRegionFile(int x, int y) const {
-	return directory/path(std::to_string(x) + "_" + std::to_string(y) + ".bin");
+	return getRegionsFolder()/path(std::to_string(x) + "_" + std::to_string(y) + ".bin");
 }
 
 path WorldFiles::getPlayerFile() const {
@@ -114,6 +120,10 @@ path WorldFiles::getWorldFile() const {
 	return directory/path("world.bin");
 }
 
+path WorldFiles::getBlockIndicesFile() const {
+	return directory/path("blocks.idx");
+}
+
 ubyte* WorldFiles::getChunk(int x, int y){
 	int regionX = floordiv(x, REGION_SIZE);
 	int regionY = floordiv(y, REGION_SIZE);
@@ -190,13 +200,15 @@ ubyte* WorldFiles::readChunkData(int x, int y, uint32_t& length){
 	return data;
 }
 
-void WorldFiles::write(const WorldInfo info){
+void WorldFiles::write(const WorldInfo info, const Content* content) {
+	path directory = getRegionsFolder();
 	if (!std::filesystem::is_directory(directory)) {
 		std::filesystem::create_directories(directory);
 	}
 	writeWorldInfo(info);
 	if (generatorTestMode)
 		return;
+	writeIndices(content->indices);
 	for (auto it = regions.begin(); it != regions.end(); it++){
 		if (it->second.chunksData == nullptr || !it->second.unsaved)
 			continue;
@@ -205,6 +217,20 @@ void WorldFiles::write(const WorldInfo info){
 	}
 }
 
+void WorldFiles::writeIndices(const ContentIndices* indices) {
+	/* Blocks indices */ {
+		BinaryWriter out;
+		uint count = indices->countBlockDefs();
+		out.putInt16(count);
+		for (uint i = 0; i < count; i++) {
+			const Block* def = indices->getBlockDef(i);
+			out.putShortStr(def->name);
+		}
+		files::write_bytes(getBlockIndicesFile(), 
+						   (const char*)out.data(), out.size());
+	}
+}
+
 void WorldFiles::writeWorldInfo(const WorldInfo& info) {
 	BinaryWriter out;
 	out.putCStr(WORLD_FORMAT_MAGIC);
diff --git a/src/files/WorldFiles.h b/src/files/WorldFiles.h
index 912f4341..5b8832a7 100644
--- a/src/files/WorldFiles.h
+++ b/src/files/WorldFiles.h
@@ -23,6 +23,8 @@
 
 class Player;
 class Chunk;
+class Content;
+class ContentIndices;
 
 struct WorldRegion {
 	ubyte** chunksData;
@@ -38,9 +40,11 @@ struct WorldInfo {
 
 class WorldFiles {
 	void writeWorldInfo(const WorldInfo& info);
+	std::filesystem::path getRegionsFolder() const;
 	std::filesystem::path getRegionFile(int x, int y) const;
 	std::filesystem::path getPlayerFile() const;
 	std::filesystem::path getWorldFile() const;
+	std::filesystem::path getBlockIndicesFile() const;
 public:
 	std::unordered_map<glm::ivec2, WorldRegion> regions;
 	std::filesystem::path directory;
@@ -58,7 +62,8 @@ public:
 	ubyte* getChunk(int x, int y);
 	void writeRegion(int x, int y, WorldRegion& entry);
 	void writePlayer(Player* player);
-	void write(const WorldInfo info);
+	void write(const WorldInfo info, const Content* content);
+	void writeIndices(const ContentIndices* indices);
 };
 
 #endif /* FILES_WORLDFILES_H_ */
\ No newline at end of file
diff --git a/src/files/binary_io.cpp b/src/files/binary_io.cpp
index 696437d0..94c8e7ba 100644
--- a/src/files/binary_io.cpp
+++ b/src/files/binary_io.cpp
@@ -27,6 +27,15 @@ void BinaryWriter::put(const string& s) {
     put((const ubyte*)s.data(), len);
 }
 
+void BinaryWriter::putShortStr(const string& s) {
+    size_t len = s.length();
+    if (len > 255) {
+        throw std::domain_error("length > 255");
+    }
+    put(len);
+    put((const ubyte*)s.data(), len);
+}
+
 void BinaryWriter::put(const ubyte* arr, size_t size) {
     buffer.reserve(buffer.size() + size);
     for (size_t i = 0; i < size; i++) {
@@ -144,6 +153,15 @@ string BinaryReader::getString() {
     return string((const char*)(data+pos-length), length);
 }
 
+string BinaryReader::getShortString() {
+    ubyte length = get();
+    if (pos+length > size) {
+        throw std::underflow_error("unexpected end");
+    }
+    pos += length;
+    return string((const char*)(data+pos-length), length);
+}
+
 bool BinaryReader::hasNext() const {
     return pos < size;
 }
diff --git a/src/files/binary_io.h b/src/files/binary_io.h
index cd68fd59..ac7a7299 100644
--- a/src/files/binary_io.h
+++ b/src/files/binary_io.h
@@ -16,6 +16,7 @@ public:
     void putFloat32(float val);
     void put(const std::string& s);
     void put(const ubyte* arr, size_t size);
+    void putShortStr(const std::string& s);
 
     inline size_t size() const {
         return buffer.size();
@@ -39,6 +40,7 @@ public:
     int64_t getInt64();
     float getFloat32();
     std::string getString();
+    std::string getShortString();
     bool hasNext() const;
 };
 
diff --git a/src/world/World.cpp b/src/world/World.cpp
index 8a1b4029..535fcbc9 100644
--- a/src/world/World.cpp
+++ b/src/world/World.cpp
@@ -5,6 +5,7 @@
 
 #include "Level.h"
 #include "../files/WorldFiles.h"
+#include "../content/Content.h"
 #include "../voxels/Chunk.h"
 #include "../voxels/Chunks.h"
 #include "../voxels/ChunksStorage.h"
@@ -29,6 +30,8 @@ World::~World(){
 }
 
 void World::write(Level* level) {
+	const Content* content = level->content;
+
 	Chunks* chunks = level->chunks;
 
 	for (size_t i = 0; i < chunks->volume; i++) {
@@ -38,7 +41,7 @@ void World::write(Level* level) {
 		wfile->put(chunk.get());
 	}
 
-	wfile->write(WorldInfo {name, wfile->directory, seed});
+	wfile->write(WorldInfo {name, wfile->directory, seed}, content);
 	wfile->writePlayer(level->player);
 }