diff --git a/build.gradle b/build.gradle
index 479ff1206..2b5b7f986 100644
--- a/build.gradle
+++ b/build.gradle
@@ -1,5 +1,6 @@
 plugins {
     id 'java'
+    id 'net.ltgt.apt' version '0.10'
 }
 
 group 'fr.themode.minestom'
@@ -12,12 +13,26 @@ repositories {
     maven { url 'https://jitpack.io' }
 }
 
+def lombokDependency = 'org.projectlombok:lombok:1.18.2'
+
+
 dependencies {
     testCompile group: 'junit', name: 'junit', version: '4.12'
+
+    compileOnly lombokDependency
+
+    apt lombokDependency
+
+    // https://mvnrepository.com/artifact/com.github.jhg023/SimpleNet
+    compile group: 'com.github.jhg023', name: 'SimpleNet', version: '1.5.1'
+    // https://mvnrepository.com/artifact/it.unimi.dsi/fastutil
+    compile group: 'it.unimi.dsi', name: 'fastutil', version: '8.3.0'
+
     compile 'com.github.Querz:NBT:4.1'
     implementation 'com.github.luben:zstd-jni:1.4.3-1'
     implementation 'com.esotericsoftware:reflectasm:1.11.9'
     implementation 'com.github.LynnOwens:starlite:9971b899f7'
-    //implementation 'com.github.jhg023:SimpleNet:1.5.0'
-    implementation 'com.github.jhg023:SimpleNet:97dbc4951e'
+    // https://mvnrepository.com/artifact/com.google.code.gson/gson
+    compile group: 'com.google.code.gson', name: 'gson', version: '2.8.5'
+
 }
diff --git a/src/main/java/fr/themode/minestom/Main.java b/src/main/java/fr/themode/minestom/Main.java
index c883156e7..8b4ec0c00 100644
--- a/src/main/java/fr/themode/minestom/Main.java
+++ b/src/main/java/fr/themode/minestom/Main.java
@@ -4,8 +4,8 @@ import com.github.simplenet.Server;
 import fr.themode.minestom.data.DataManager;
 import fr.themode.minestom.entity.EntityManager;
 import fr.themode.minestom.entity.Player;
-import fr.themode.minestom.instance.BlockManager;
 import fr.themode.minestom.instance.InstanceManager;
+import fr.themode.minestom.instance.block.BlockManager;
 import fr.themode.minestom.instance.demo.StoneBlock;
 import fr.themode.minestom.listener.PacketListenerManager;
 import fr.themode.minestom.net.ConnectionManager;
@@ -22,7 +22,6 @@ public class Main {
     // Thread number
     public static final int THREAD_COUNT_PACKET_WRITER = 2;
     public static final int THREAD_COUNT_IO = 2;
-    public static final int THREAD_COUNT_CHUNK_BATCH = 2;
     public static final int THREAD_COUNT_BLOCK_BATCH = 2;
     public static final int THREAD_COUNT_ENTITIES = 2;
     public static final int THREAD_COUNT_PLAYERS_ENTITIES = 2;
@@ -64,7 +63,7 @@ public class Main {
             System.out.println("CONNECTION");
 
             client.preDisconnect(() -> {
-                System.out.println("A Disconnection");
+                System.out.println("DISCONNECTION");
                 PlayerConnection playerConnection = packetProcessor.getPlayerConnection(client);
                 if (playerConnection != null) {
                     playerConnection.refreshOnline(false);
@@ -115,6 +114,11 @@ public class Main {
             // Entities update
             entityManager.update();
 
+            // Blocks update
+            blockManager.update();
+
+            // TODO miscellaneous update (scoreboard)
+
             // Sleep until next tick
             long sleepTime = (tickDistance - (System.nanoTime() - currentTime)) / 1000000;
             sleepTime = Math.max(1, sleepTime);
diff --git a/src/main/java/fr/themode/minestom/chat/ChatColor.java b/src/main/java/fr/themode/minestom/chat/ChatColor.java
new file mode 100644
index 000000000..2cacc1d42
--- /dev/null
+++ b/src/main/java/fr/themode/minestom/chat/ChatColor.java
@@ -0,0 +1,35 @@
+package fr.themode.minestom.chat;
+
+import fr.themode.minestom.utils.HexUtils;
+
+public enum ChatColor {
+
+    BLACK((byte) 0),
+    DARK_BLUE((byte) 1),
+    DARK_GREEN((byte) 2),
+    DARK_AQUA((byte) 3),
+    DARK_RED((byte) 4),
+    DARK_PURPLE((byte) 5),
+    GOLD((byte) 6),
+    GRAY((byte) 7),
+    DARK_GRAY((byte) 8),
+    BLUE((byte) 9),
+    GREEN((byte) 0xa),
+    AQUA((byte) 0xb),
+    RED((byte) 0xc),
+    LIGHT_PURPLE((byte) 0xd),
+    YELLOW((byte) 0xe),
+    WHITE((byte) 0xf);
+
+
+    private byte id;
+
+    ChatColor(byte id) {
+        this.id = id;
+    }
+
+    @Override
+    public String toString() {
+        return Chat.COLOR_CHAR + String.valueOf(HexUtils.byteToHex(id));
+    }
+}
diff --git a/src/main/java/fr/themode/minestom/entity/Entity.java b/src/main/java/fr/themode/minestom/entity/Entity.java
index fc59ff63b..461ee7a37 100644
--- a/src/main/java/fr/themode/minestom/entity/Entity.java
+++ b/src/main/java/fr/themode/minestom/entity/Entity.java
@@ -204,21 +204,20 @@ public abstract class Entity implements Viewable, DataContainer {
 
             // Velocity
             if (velocityTime != 0) {
+                if (this instanceof Player) {
+                    sendPacketToViewersAndSelf(getVelocityPacket());
+                } else {
+                    float tps = Main.TICK_PER_SECOND;
+                    refreshPosition(position.getX() + velocity.getX() / tps, position.getY() + velocity.getY() / tps, position.getZ() + velocity.getZ() / tps);
+                    if (this instanceof ObjectEntity) {
+                        sendPacketToViewers(getVelocityPacket());
+                    } else if (this instanceof EntityCreature) {
+                        teleport(getPosition());
+                    }
+                }
                 if (time >= velocityTime) {
                     sendSynchronization(); // Send synchronization after velocity ended
                     resetVelocity();
-                } else {
-                    if (this instanceof Player) {
-                        sendPacketToViewersAndSelf(getVelocityPacket());
-                    } else {
-                        float tps = Main.TICK_PER_SECOND;
-                        refreshPosition(position.getX() + velocity.getX() / tps, position.getY() + velocity.getY() / tps, position.getZ() + velocity.getZ() / tps);
-                        if (this instanceof ObjectEntity) {
-                            sendPacketToViewers(getVelocityPacket());
-                        } else if (this instanceof EntityCreature) {
-                            teleport(getPosition());
-                        }
-                    }
                 }
             }
 
diff --git a/src/main/java/fr/themode/minestom/entity/ItemEntity.java b/src/main/java/fr/themode/minestom/entity/ItemEntity.java
index 5fb2dc378..dc0272172 100644
--- a/src/main/java/fr/themode/minestom/entity/ItemEntity.java
+++ b/src/main/java/fr/themode/minestom/entity/ItemEntity.java
@@ -18,7 +18,7 @@ public class ItemEntity extends ObjectEntity {
         super(34);
         this.itemStack = itemStack;
         setBoundingBox(0.25f, 0.25f, 0.25f);
-        setGravity(0.02f);
+        setGravity(0.025f);
     }
 
     @Override
diff --git a/src/main/java/fr/themode/minestom/entity/LivingEntity.java b/src/main/java/fr/themode/minestom/entity/LivingEntity.java
index c6b7610ff..71c385779 100644
--- a/src/main/java/fr/themode/minestom/entity/LivingEntity.java
+++ b/src/main/java/fr/themode/minestom/entity/LivingEntity.java
@@ -153,8 +153,12 @@ public abstract class LivingEntity extends Entity {
         for (int i = 0; i < length; i++) {
             Attribute attribute = Attribute.values()[i];
             EntityPropertiesPacket.Property property = new EntityPropertiesPacket.Property();
+            float maxValue = attribute.getMaxVanillaValue();
+            float value = getAttributeValue(attribute);
+            value = value > maxValue ? maxValue : value; // Bypass vanilla limit client-side if needed (by sending the max value allowed)
+
             property.key = attribute.getKey();
-            property.value = getAttributeValue(attribute);
+            property.value = value;
             properties[i] = property;
         }
 
diff --git a/src/main/java/fr/themode/minestom/entity/Player.java b/src/main/java/fr/themode/minestom/entity/Player.java
index 1f2ae3a55..25d6c14f7 100644
--- a/src/main/java/fr/themode/minestom/entity/Player.java
+++ b/src/main/java/fr/themode/minestom/entity/Player.java
@@ -9,9 +9,9 @@ import fr.themode.minestom.collision.BoundingBox;
 import fr.themode.minestom.entity.property.Attribute;
 import fr.themode.minestom.event.*;
 import fr.themode.minestom.instance.Chunk;
-import fr.themode.minestom.instance.CustomBlock;
 import fr.themode.minestom.instance.Instance;
 import fr.themode.minestom.instance.InstanceContainer;
+import fr.themode.minestom.instance.block.CustomBlock;
 import fr.themode.minestom.instance.demo.ChunkGeneratorDemo;
 import fr.themode.minestom.inventory.Inventory;
 import fr.themode.minestom.inventory.PlayerInventory;
@@ -20,7 +20,6 @@ import fr.themode.minestom.net.packet.client.ClientPlayPacket;
 import fr.themode.minestom.net.packet.server.ServerPacket;
 import fr.themode.minestom.net.packet.server.play.*;
 import fr.themode.minestom.net.player.PlayerConnection;
-import fr.themode.minestom.scoreboard.Scoreboard;
 import fr.themode.minestom.utils.*;
 import fr.themode.minestom.world.Dimension;
 import fr.themode.minestom.world.LevelType;
@@ -145,7 +144,7 @@ public class Player extends LivingEntity {
         });
 
         setEventCallback(PlayerSpawnEvent.class, event -> {
-            setGameMode(GameMode.CREATIVE);
+            setGameMode(GameMode.SURVIVAL);
             teleport(new Position(0, 66, 0));
 
             /*Random random = new Random();
@@ -183,14 +182,12 @@ public class Player extends LivingEntity {
             setAttribute(Attribute.MAX_HEALTH, 10);
             heal();
 
-            setExp(0.9f);
-
-            Scoreboard scoreboard = new Scoreboard("Scoreboard Title");
+            /*Scoreboard scoreboard = new Scoreboard("Scoreboard Title");
             for (int i = 0; i < 15; i++) {
                 scoreboard.createLine(new Scoreboard.ScoreboardLine("id" + i, "Hey guys " + i, i));
             }
             scoreboard.addViewer(this);
-            scoreboard.updateLineContent("id3", "I HAVE BEEN UPDATED &2TEST");
+            scoreboard.updateLineContent("id3", "I HAVE BEEN UPDATED &2TEST");*/
         });
     }
 
diff --git a/src/main/java/fr/themode/minestom/entity/property/Attribute.java b/src/main/java/fr/themode/minestom/entity/property/Attribute.java
index db121c309..299de52b7 100644
--- a/src/main/java/fr/themode/minestom/entity/property/Attribute.java
+++ b/src/main/java/fr/themode/minestom/entity/property/Attribute.java
@@ -2,22 +2,24 @@ package fr.themode.minestom.entity.property;
 
 public enum Attribute {
 
-    MAX_HEALTH("generic.maxHealth", 20),
-    FOLLOW_RANGE("generic.followRange", 32),
-    KNOCKBACK_RESISTANCE("generic.knockbackResistance", 0),
-    MOVEMENT_SPEED("generic.movementSpeed", 0.7f),
-    ATTACK_DAMAGE("generic.attackDamage", 2),
-    ATTACK_SPEED("generic.attackSpeed", 4),
-    FLYING_SPEED("generic.flyingSpeed", 0.4f),
-    HORSE_JUMP_STRENGTH("horse.jumpStrength", 0.7f),
-    ZOMBIE_SPAWN_REINFORCEMENTS("zombie.spawnReinforcements", 0);
+    MAX_HEALTH("generic.maxHealth", 20, 1024),
+    FOLLOW_RANGE("generic.followRange", 32, 2048),
+    KNOCKBACK_RESISTANCE("generic.knockbackResistance", 0, 1),
+    MOVEMENT_SPEED("generic.movementSpeed", 0.7f, 1024),
+    ATTACK_DAMAGE("generic.attackDamage", 2, 2048),
+    ATTACK_SPEED("generic.attackSpeed", 4, 1024),
+    FLYING_SPEED("generic.flyingSpeed", 0.4f, 1024),
+    HORSE_JUMP_STRENGTH("horse.jumpStrength", 0.7f, 2),
+    ZOMBIE_SPAWN_REINFORCEMENTS("zombie.spawnReinforcements", 0, 1);
 
     private String key;
     private float defaultValue;
+    private float maxVanillaValue;
 
-    Attribute(String key, float defaultValue) {
+    Attribute(String key, float defaultValue, float maxVanillaValue) {
         this.key = key;
         this.defaultValue = defaultValue;
+        this.maxVanillaValue = maxVanillaValue;
     }
 
     public String getKey() {
@@ -27,4 +29,8 @@ public enum Attribute {
     public float getDefaultValue() {
         return defaultValue;
     }
+
+    public float getMaxVanillaValue() {
+        return maxVanillaValue;
+    }
 }
diff --git a/src/main/java/fr/themode/minestom/event/PlayerStartDiggingEvent.java b/src/main/java/fr/themode/minestom/event/PlayerStartDiggingEvent.java
index 018dcbcf7..e52516c7b 100644
--- a/src/main/java/fr/themode/minestom/event/PlayerStartDiggingEvent.java
+++ b/src/main/java/fr/themode/minestom/event/PlayerStartDiggingEvent.java
@@ -1,6 +1,6 @@
 package fr.themode.minestom.event;
 
-import fr.themode.minestom.instance.CustomBlock;
+import fr.themode.minestom.instance.block.CustomBlock;
 
 public class PlayerStartDiggingEvent extends CancellableEvent {
 
diff --git a/src/main/java/fr/themode/minestom/instance/Chunk.java b/src/main/java/fr/themode/minestom/instance/Chunk.java
index 7a88f083e..f7c396fbc 100644
--- a/src/main/java/fr/themode/minestom/instance/Chunk.java
+++ b/src/main/java/fr/themode/minestom/instance/Chunk.java
@@ -3,7 +3,9 @@ package fr.themode.minestom.instance;
 import com.github.simplenet.packet.Packet;
 import fr.themode.minestom.Main;
 import fr.themode.minestom.Viewable;
+import fr.themode.minestom.data.Data;
 import fr.themode.minestom.entity.Player;
+import fr.themode.minestom.instance.block.CustomBlock;
 import fr.themode.minestom.net.packet.server.play.ChunkDataPacket;
 import fr.themode.minestom.utils.PacketUtils;
 import fr.themode.minestom.utils.SerializerUtils;
@@ -14,7 +16,9 @@ import java.io.IOException;
 import java.util.Collections;
 import java.util.Set;
 import java.util.concurrent.CopyOnWriteArraySet;
+import java.util.function.Consumer;
 
+// TODO air management to free memory
 public class Chunk implements Viewable {
 
     public static final int CHUNK_SIZE_X = 16;
@@ -30,6 +34,8 @@ public class Chunk implements Viewable {
     // Block entities
     private Set<Integer> blockEntities = new CopyOnWriteArraySet<>();
 
+    // TODO blocks update
+
     // Cache
     private Set<Player> viewers = new CopyOnWriteArraySet<>();
     private Packet fullDataPacket;
@@ -42,16 +48,16 @@ public class Chunk implements Viewable {
         this.chunkZ = chunkZ;
     }
 
-    protected void setBlock(byte x, byte y, byte z, short blockId) {
+    public void UNSAFE_setBlock(byte x, byte y, byte z, short blockId) {
         setBlock(x, y, z, blockId, (short) 0);
     }
 
-    protected void setCustomBlock(byte x, byte y, byte z, String blockId) {
+    public void UNSAFE_setCustomBlock(byte x, byte y, byte z, String blockId) {
         CustomBlock customBlock = Main.getBlockManager().getBlock(blockId);
         if (customBlock == null)
             throw new IllegalArgumentException("The block " + blockId + " does not exist or isn't registered");
 
-        setBlock(x, y, z, customBlock.getType(), customBlock.getId());
+        setCustomBlock(x, y, z, customBlock);
     }
 
     protected void setCustomBlock(byte x, byte y, byte z, short customBlockId) {
@@ -59,7 +65,7 @@ public class Chunk implements Viewable {
         if (customBlock == null)
             throw new IllegalArgumentException("The custom block " + customBlockId + " does not exist or isn't registered");
 
-        setBlock(x, y, z, customBlock.getType(), customBlockId);
+        setCustomBlock(x, y, z, customBlock);
     }
 
     private void setBlock(byte x, byte y, byte z, short blockType, short customId) {
@@ -74,6 +80,14 @@ public class Chunk implements Viewable {
         this.packetUpdated = false;
     }
 
+    private void setCustomBlock(byte x, byte y, byte z, CustomBlock customBlock) {
+        if (customBlock.hasUpdate()) {
+            Consumer<Data> test = customBlock::update;
+            // TODO add update callback
+        }
+        setBlock(x, y, z, customBlock.getType(), customBlock.getId());
+    }
+
     public short getBlockId(byte x, byte y, byte z) {
         return this.blocksId[SerializerUtils.chunkCoordToIndex(x, y, z)];
     }
@@ -83,6 +97,17 @@ public class Chunk implements Viewable {
         return id != 0 ? Main.getBlockManager().getBlock(id) : null;
     }
 
+    public void updateBlocks() {
+        /**
+         * TODO blocks' update:
+         *  - get all custom blocks
+         *  - check if they have an update method
+         *  - check if they should be updated
+         *  - get custom block's data
+         *  - call update method
+         */
+    }
+
     public Biome getBiome() {
         return biome;
     }
@@ -110,6 +135,7 @@ public class Chunk implements Viewable {
 
     public void setFullDataPacket(Packet fullDataPacket) {
         this.fullDataPacket = fullDataPacket;
+        this.packetUpdated = true;
     }
 
     protected byte[] getSerializedData() throws IOException {
@@ -153,10 +179,9 @@ public class Chunk implements Viewable {
     }
 
     // Write the packet in the current thread
-    protected void refreshDataPacket() {
+    public void refreshDataPacket() {
         PacketUtils.writePacket(getFreshFullDataPacket(), packet -> {
-            fullDataPacket = packet;
-            packetUpdated = true;
+            setFullDataPacket(packet);
         });
     }
 
diff --git a/src/main/java/fr/themode/minestom/instance/ChunkGenerator.java b/src/main/java/fr/themode/minestom/instance/ChunkGenerator.java
index 212e5fee0..29bbae53b 100644
--- a/src/main/java/fr/themode/minestom/instance/ChunkGenerator.java
+++ b/src/main/java/fr/themode/minestom/instance/ChunkGenerator.java
@@ -1,5 +1,7 @@
 package fr.themode.minestom.instance;
 
+import fr.themode.minestom.instance.batch.ChunkBatch;
+
 public abstract class ChunkGenerator {
 
     public abstract void generateChunkData(ChunkBatch batch, int chunkX, int chunkZ);
diff --git a/src/main/java/fr/themode/minestom/instance/ChunkLoaderIO.java b/src/main/java/fr/themode/minestom/instance/ChunkLoaderIO.java
index cf1272cf9..fcc1289ca 100644
--- a/src/main/java/fr/themode/minestom/instance/ChunkLoaderIO.java
+++ b/src/main/java/fr/themode/minestom/instance/ChunkLoaderIO.java
@@ -69,7 +69,7 @@ public class ChunkLoaderIO {
                     if (isCustomBlock) {
                         chunk.setCustomBlock(chunkPos[0], chunkPos[1], chunkPos[2], blockId);
                     } else {
-                        chunk.setBlock(chunkPos[0], chunkPos[1], chunkPos[2], blockId);
+                        chunk.UNSAFE_setBlock(chunkPos[0], chunkPos[1], chunkPos[2], blockId);
                     }
                 }
             } catch (EOFException e) {
diff --git a/src/main/java/fr/themode/minestom/instance/Instance.java b/src/main/java/fr/themode/minestom/instance/Instance.java
index b57490358..e5bb944cd 100644
--- a/src/main/java/fr/themode/minestom/instance/Instance.java
+++ b/src/main/java/fr/themode/minestom/instance/Instance.java
@@ -3,6 +3,9 @@ package fr.themode.minestom.instance;
 import com.github.simplenet.packet.Packet;
 import fr.themode.minestom.Main;
 import fr.themode.minestom.entity.*;
+import fr.themode.minestom.instance.batch.BlockBatch;
+import fr.themode.minestom.instance.batch.ChunkBatch;
+import fr.themode.minestom.instance.block.CustomBlock;
 import fr.themode.minestom.net.PacketWriterUtils;
 import fr.themode.minestom.net.packet.server.play.ChunkDataPacket;
 import fr.themode.minestom.utils.BlockPosition;
diff --git a/src/main/java/fr/themode/minestom/instance/InstanceContainer.java b/src/main/java/fr/themode/minestom/instance/InstanceContainer.java
index ebba125f6..5a736fa76 100644
--- a/src/main/java/fr/themode/minestom/instance/InstanceContainer.java
+++ b/src/main/java/fr/themode/minestom/instance/InstanceContainer.java
@@ -3,6 +3,8 @@ package fr.themode.minestom.instance;
 import com.github.simplenet.packet.Packet;
 import fr.themode.minestom.entity.Player;
 import fr.themode.minestom.event.PlayerBlockBreakEvent;
+import fr.themode.minestom.instance.batch.BlockBatch;
+import fr.themode.minestom.instance.batch.ChunkBatch;
 import fr.themode.minestom.net.PacketWriterUtils;
 import fr.themode.minestom.net.packet.server.play.BlockChangePacket;
 import fr.themode.minestom.net.packet.server.play.ParticlePacket;
@@ -41,7 +43,7 @@ public class InstanceContainer extends Instance {
             byte chunkX = (byte) (x % 16);
             byte chunkY = (byte) y;
             byte chunkZ = (byte) (z % 16);
-            chunk.setBlock(chunkX, chunkY, chunkZ, blockId);
+            chunk.UNSAFE_setBlock(chunkX, chunkY, chunkZ, blockId);
             sendBlockChange(chunk, x, y, z, blockId);
         }
     }
@@ -53,7 +55,7 @@ public class InstanceContainer extends Instance {
             byte chunkX = (byte) (x % 16);
             byte chunkY = (byte) y;
             byte chunkZ = (byte) (z % 16);
-            chunk.setCustomBlock(chunkX, chunkY, chunkZ, blockId);
+            chunk.UNSAFE_setCustomBlock(chunkX, chunkY, chunkZ, blockId);
             short id = chunk.getBlockId(chunkX, chunkY, chunkZ);
             sendBlockChange(chunk, x, y, z, id);
         }
@@ -199,7 +201,6 @@ public class InstanceContainer extends Instance {
         if (data == null || !chunk.packetUpdated) {
             PacketWriterUtils.writeCallbackPacket(chunk.getFreshFullDataPacket(), buffer -> {
                 chunk.setFullDataPacket(buffer);
-                chunk.packetUpdated = true;
                 sendChunkUpdate(player, chunk);
             });
         } else {
diff --git a/src/main/java/fr/themode/minestom/instance/SharedInstance.java b/src/main/java/fr/themode/minestom/instance/SharedInstance.java
index f147f25a3..3912d2c6a 100644
--- a/src/main/java/fr/themode/minestom/instance/SharedInstance.java
+++ b/src/main/java/fr/themode/minestom/instance/SharedInstance.java
@@ -1,6 +1,8 @@
 package fr.themode.minestom.instance;
 
 import fr.themode.minestom.entity.Player;
+import fr.themode.minestom.instance.batch.BlockBatch;
+import fr.themode.minestom.instance.batch.ChunkBatch;
 import fr.themode.minestom.utils.BlockPosition;
 
 import java.io.File;
diff --git a/src/main/java/fr/themode/minestom/instance/BlockBatch.java b/src/main/java/fr/themode/minestom/instance/batch/BlockBatch.java
similarity index 82%
rename from src/main/java/fr/themode/minestom/instance/BlockBatch.java
rename to src/main/java/fr/themode/minestom/instance/batch/BlockBatch.java
index 21ba03d9f..9c0898c95 100644
--- a/src/main/java/fr/themode/minestom/instance/BlockBatch.java
+++ b/src/main/java/fr/themode/minestom/instance/batch/BlockBatch.java
@@ -1,17 +1,15 @@
-package fr.themode.minestom.instance;
+package fr.themode.minestom.instance.batch;
 
-import fr.themode.minestom.Main;
-import fr.themode.minestom.utils.thread.MinestomThread;
+import fr.themode.minestom.instance.BlockModifier;
+import fr.themode.minestom.instance.Chunk;
+import fr.themode.minestom.instance.InstanceContainer;
 
 import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
-import java.util.concurrent.ExecutorService;
 
-public class BlockBatch implements BlockModifier {
-
-    private static final ExecutorService batchesPool = new MinestomThread(Main.THREAD_COUNT_BLOCK_BATCH, "Ms-BlockBatchPool");
+public class BlockBatch implements IBatch, BlockModifier {
 
     private InstanceContainer instance;
 
@@ -85,9 +83,9 @@ public class BlockBatch implements BlockModifier {
 
         public void apply(Chunk chunk) {
             if (blockIdentifier == null) {
-                chunk.setBlock((byte) x, (byte) y, (byte) z, blockId);
+                chunk.UNSAFE_setBlock((byte) x, (byte) y, (byte) z, blockId);
             } else {
-                chunk.setCustomBlock((byte) x, (byte) y, (byte) z, blockIdentifier);
+                chunk.UNSAFE_setCustomBlock((byte) x, (byte) y, (byte) z, blockIdentifier);
             }
         }
 
diff --git a/src/main/java/fr/themode/minestom/instance/ChunkBatch.java b/src/main/java/fr/themode/minestom/instance/batch/ChunkBatch.java
similarity index 81%
rename from src/main/java/fr/themode/minestom/instance/ChunkBatch.java
rename to src/main/java/fr/themode/minestom/instance/batch/ChunkBatch.java
index 063a8dbaa..35f682fbe 100644
--- a/src/main/java/fr/themode/minestom/instance/ChunkBatch.java
+++ b/src/main/java/fr/themode/minestom/instance/batch/ChunkBatch.java
@@ -1,19 +1,18 @@
-package fr.themode.minestom.instance;
+package fr.themode.minestom.instance.batch;
 
-import fr.themode.minestom.Main;
-import fr.themode.minestom.utils.thread.MinestomThread;
+import fr.themode.minestom.instance.BlockModifier;
+import fr.themode.minestom.instance.Chunk;
+import fr.themode.minestom.instance.ChunkGenerator;
+import fr.themode.minestom.instance.InstanceContainer;
 
 import java.util.ArrayList;
 import java.util.List;
-import java.util.concurrent.ExecutorService;
 import java.util.function.Consumer;
 
 /**
  * Use chunk coordinate (0-16) instead of world's
  */
-public class ChunkBatch implements BlockModifier {
-
-    private static final ExecutorService batchesPool = new MinestomThread(Main.THREAD_COUNT_CHUNK_BATCH, "Ms-ChunkBatchPool");
+public class ChunkBatch implements IBatch, BlockModifier {
 
     private InstanceContainer instance;
     private Chunk chunk;
@@ -82,9 +81,9 @@ public class ChunkBatch implements BlockModifier {
 
         public void apply(Chunk chunk) {
             if (blockIdentifier == null) {
-                chunk.setBlock(x, y, z, blockId);
+                chunk.UNSAFE_setBlock(x, y, z, blockId);
             } else {
-                chunk.setCustomBlock(x, y, z, blockIdentifier);
+                chunk.UNSAFE_setCustomBlock(x, y, z, blockIdentifier);
             }
         }
 
diff --git a/src/main/java/fr/themode/minestom/instance/batch/IBatch.java b/src/main/java/fr/themode/minestom/instance/batch/IBatch.java
new file mode 100644
index 000000000..f28c6949b
--- /dev/null
+++ b/src/main/java/fr/themode/minestom/instance/batch/IBatch.java
@@ -0,0 +1,12 @@
+package fr.themode.minestom.instance.batch;
+
+import fr.themode.minestom.Main;
+import fr.themode.minestom.utils.thread.MinestomThread;
+
+import java.util.concurrent.ExecutorService;
+
+public interface IBatch {
+
+    ExecutorService batchesPool = new MinestomThread(Main.THREAD_COUNT_BLOCK_BATCH, "Ms-BlockBatchPool");
+
+}
diff --git a/src/main/java/fr/themode/minestom/instance/BlockManager.java b/src/main/java/fr/themode/minestom/instance/block/BlockManager.java
similarity index 57%
rename from src/main/java/fr/themode/minestom/instance/BlockManager.java
rename to src/main/java/fr/themode/minestom/instance/block/BlockManager.java
index 632ef4143..53d1d4d43 100644
--- a/src/main/java/fr/themode/minestom/instance/BlockManager.java
+++ b/src/main/java/fr/themode/minestom/instance/block/BlockManager.java
@@ -1,4 +1,9 @@
-package fr.themode.minestom.instance;
+package fr.themode.minestom.instance.block;
+
+import fr.themode.minestom.Main;
+import fr.themode.minestom.instance.Chunk;
+import fr.themode.minestom.instance.Instance;
+import fr.themode.minestom.instance.InstanceManager;
 
 import java.util.HashMap;
 import java.util.Map;
@@ -6,6 +11,8 @@ import java.util.function.Supplier;
 
 public class BlockManager {
 
+    private static InstanceManager instanceManager = Main.getInstanceManager();
+
     private Map<Short, CustomBlock> blocksInternalId = new HashMap<>();
     private Map<String, CustomBlock> blocksId = new HashMap<>();
 
@@ -17,6 +24,15 @@ public class BlockManager {
         this.blocksId.put(identifier, customBlock);
     }
 
+    public void update() {
+        for (Instance instance : instanceManager.getInstances()) {
+            // TODO only InstanceContainer?
+            for (Chunk chunk : instance.getChunks()) {
+                chunk.updateBlocks();
+            }
+        }
+    }
+
     public CustomBlock getBlock(String identifier) {
         return blocksId.get(identifier);
     }
diff --git a/src/main/java/fr/themode/minestom/instance/CustomBlock.java b/src/main/java/fr/themode/minestom/instance/block/CustomBlock.java
similarity index 66%
rename from src/main/java/fr/themode/minestom/instance/CustomBlock.java
rename to src/main/java/fr/themode/minestom/instance/block/CustomBlock.java
index a2eef14c3..199a65208 100644
--- a/src/main/java/fr/themode/minestom/instance/CustomBlock.java
+++ b/src/main/java/fr/themode/minestom/instance/block/CustomBlock.java
@@ -1,5 +1,6 @@
-package fr.themode.minestom.instance;
+package fr.themode.minestom.instance.block;
 
+import fr.themode.minestom.data.Data;
 import fr.themode.minestom.entity.Player;
 
 import java.util.concurrent.atomic.AtomicInteger;
@@ -18,6 +19,12 @@ public abstract class CustomBlock {
         this.id = (short) idCounter.incrementAndGet();
     }
 
+    public void update(Data data) {
+        throw new UnsupportedOperationException("Update method not overriden");
+    }
+
+    public abstract UpdateOption getUpdateOption();
+
     public abstract short getType();
 
     public abstract String getIdentifier();
@@ -27,6 +34,10 @@ public abstract class CustomBlock {
      */
     public abstract int getBreakDelay(Player player);
 
+    public boolean hasUpdate() {
+        return getUpdateOption().getValue() > 0;
+    }
+
     public short getId() {
         return id;
     }
diff --git a/src/main/java/fr/themode/minestom/instance/block/UpdateOption.java b/src/main/java/fr/themode/minestom/instance/block/UpdateOption.java
new file mode 100644
index 000000000..bd900c25b
--- /dev/null
+++ b/src/main/java/fr/themode/minestom/instance/block/UpdateOption.java
@@ -0,0 +1,26 @@
+package fr.themode.minestom.instance.block;
+
+import fr.themode.minestom.timer.TimeUnit;
+
+public class UpdateOption {
+
+    private int value;
+    private TimeUnit timeUnit;
+
+    public UpdateOption(int value, TimeUnit timeUnit) {
+        this.value = value;
+        this.timeUnit = timeUnit;
+    }
+
+    public UpdateOption() {
+        this(0, null);
+    }
+
+    public int getValue() {
+        return value;
+    }
+
+    public TimeUnit getTimeUnit() {
+        return timeUnit;
+    }
+}
diff --git a/src/main/java/fr/themode/minestom/instance/demo/ChunkGeneratorDemo.java b/src/main/java/fr/themode/minestom/instance/demo/ChunkGeneratorDemo.java
index fcdd8c526..d13759699 100644
--- a/src/main/java/fr/themode/minestom/instance/demo/ChunkGeneratorDemo.java
+++ b/src/main/java/fr/themode/minestom/instance/demo/ChunkGeneratorDemo.java
@@ -1,8 +1,8 @@
 package fr.themode.minestom.instance.demo;
 
 import fr.themode.minestom.instance.Biome;
-import fr.themode.minestom.instance.ChunkBatch;
 import fr.themode.minestom.instance.ChunkGenerator;
+import fr.themode.minestom.instance.batch.ChunkBatch;
 
 import java.util.Random;
 
diff --git a/src/main/java/fr/themode/minestom/instance/demo/StoneBlock.java b/src/main/java/fr/themode/minestom/instance/demo/StoneBlock.java
index 80cef0c35..20a5d49a8 100644
--- a/src/main/java/fr/themode/minestom/instance/demo/StoneBlock.java
+++ b/src/main/java/fr/themode/minestom/instance/demo/StoneBlock.java
@@ -1,10 +1,25 @@
 package fr.themode.minestom.instance.demo;
 
+import fr.themode.minestom.data.Data;
 import fr.themode.minestom.entity.Player;
-import fr.themode.minestom.instance.CustomBlock;
+import fr.themode.minestom.instance.block.CustomBlock;
+import fr.themode.minestom.instance.block.UpdateOption;
+import fr.themode.minestom.timer.TimeUnit;
 
 public class StoneBlock extends CustomBlock {
 
+    private static final UpdateOption UPDATE_OPTION = new UpdateOption(1, TimeUnit.TICK);
+
+    @Override
+    public UpdateOption getUpdateOption() {
+        return UPDATE_OPTION;
+    }
+
+    @Override
+    public void update(Data data) {
+        System.out.println("BLOCK HAS BEEN UPDATED");
+    }
+
     @Override
     public short getType() {
         return 1;
diff --git a/src/main/java/fr/themode/minestom/listener/BlockPlacementListener.java b/src/main/java/fr/themode/minestom/listener/BlockPlacementListener.java
index 282d9b88b..2998a4370 100644
--- a/src/main/java/fr/themode/minestom/listener/BlockPlacementListener.java
+++ b/src/main/java/fr/themode/minestom/listener/BlockPlacementListener.java
@@ -1,5 +1,6 @@
 package fr.themode.minestom.listener;
 
+import fr.themode.minestom.entity.GameMode;
 import fr.themode.minestom.entity.Player;
 import fr.themode.minestom.event.PlayerBlockPlaceEvent;
 import fr.themode.minestom.instance.Chunk;
@@ -37,6 +38,8 @@ public class BlockPlacementListener {
         boolean intersectPlayer = player.getBoundingBox().intersect(blockPosition); // TODO check if collide with nearby players
         if (!intersectPlayer) {
             PlayerBlockPlaceEvent playerBlockPlaceEvent = new PlayerBlockPlaceEvent((short) 10, blockPosition, packet.hand);
+            playerBlockPlaceEvent.consumeBlock(player.getGameMode() != GameMode.CREATIVE);
+
             player.callEvent(PlayerBlockPlaceEvent.class, playerBlockPlaceEvent);
             if (!playerBlockPlaceEvent.isCancelled()) {
                 instance.setBlock(blockPosition, "custom_block"); // TODO set useItem's block instead
diff --git a/src/main/java/fr/themode/minestom/listener/KeepAliveListener.java b/src/main/java/fr/themode/minestom/listener/KeepAliveListener.java
index c4d0b757a..28879ef09 100644
--- a/src/main/java/fr/themode/minestom/listener/KeepAliveListener.java
+++ b/src/main/java/fr/themode/minestom/listener/KeepAliveListener.java
@@ -1,5 +1,6 @@
 package fr.themode.minestom.listener;
 
+import fr.themode.minestom.chat.ChatColor;
 import fr.themode.minestom.entity.Player;
 import fr.themode.minestom.net.packet.client.play.ClientKeepAlivePacket;
 
@@ -7,7 +8,7 @@ public class KeepAliveListener {
 
     public static void listener(ClientKeepAlivePacket packet, Player player) {
         if (packet.id != player.getLastKeepAlive()) {
-            player.kick("Bad Keep Alive packet");
+            player.kick(ChatColor.RED + "Bad Keep Alive packet");
         }
     }
 
diff --git a/src/main/java/fr/themode/minestom/listener/PlayerDiggingListener.java b/src/main/java/fr/themode/minestom/listener/PlayerDiggingListener.java
index 4311c2255..e1c2152ce 100644
--- a/src/main/java/fr/themode/minestom/listener/PlayerDiggingListener.java
+++ b/src/main/java/fr/themode/minestom/listener/PlayerDiggingListener.java
@@ -5,8 +5,8 @@ import fr.themode.minestom.entity.ItemEntity;
 import fr.themode.minestom.entity.Player;
 import fr.themode.minestom.event.ItemDropEvent;
 import fr.themode.minestom.event.PlayerStartDiggingEvent;
-import fr.themode.minestom.instance.CustomBlock;
 import fr.themode.minestom.instance.Instance;
+import fr.themode.minestom.instance.block.CustomBlock;
 import fr.themode.minestom.inventory.PlayerInventory;
 import fr.themode.minestom.item.ItemStack;
 import fr.themode.minestom.net.packet.client.play.ClientPlayerDiggingPacket;
diff --git a/src/main/java/fr/themode/minestom/timer/TimeUnit.java b/src/main/java/fr/themode/minestom/timer/TimeUnit.java
new file mode 100644
index 000000000..c1b080f36
--- /dev/null
+++ b/src/main/java/fr/themode/minestom/timer/TimeUnit.java
@@ -0,0 +1,21 @@
+package fr.themode.minestom.timer;
+
+import fr.themode.minestom.Main;
+
+public enum TimeUnit {
+
+    TICK, MILLISECOND, SECOND;
+
+    public long toMilliseconds(int value) {
+        switch (this) {
+            case TICK:
+                return Main.TICK_MS * value;
+            case SECOND:
+                return value * 1000;
+            case MILLISECOND:
+                return value;
+        }
+        return -1; // Unexpected
+    }
+
+}
diff --git a/src/main/java/fr/themode/minestom/utils/HexUtils.java b/src/main/java/fr/themode/minestom/utils/HexUtils.java
new file mode 100644
index 000000000..90f524d22
--- /dev/null
+++ b/src/main/java/fr/themode/minestom/utils/HexUtils.java
@@ -0,0 +1,13 @@
+package fr.themode.minestom.utils;
+
+public class HexUtils {
+
+    private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
+
+    public static char byteToHex(byte b) {
+        int v = b & 0xFF;
+        char hexChar = HEX_ARRAY[v >>> 4];
+        return hexChar;
+    }
+
+}