diff --git a/src/main/java/de/bixilon/minosoft/data/ChangeableIdentifier.java b/src/main/java/de/bixilon/minosoft/data/ChangeableIdentifier.java
index 16007af36..8b7448c11 100644
--- a/src/main/java/de/bixilon/minosoft/data/ChangeableIdentifier.java
+++ b/src/main/java/de/bixilon/minosoft/data/ChangeableIdentifier.java
@@ -37,11 +37,11 @@ public class ChangeableIdentifier extends VersionValueMap<String> {
     }
 
     public ChangeableIdentifier(IdentifierSet... sets) {
-        super(sets, true);
+        super(sets);
     }
 
     public ChangeableIdentifier(String name) {
-        super(name);
+        super(new MapSet<>(Versions.LOWEST_VERSION_SUPPORTED.getVersionId(), name));
     }
 
     public boolean isValidName(String name, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/data/VersionValueMap.java b/src/main/java/de/bixilon/minosoft/data/VersionValueMap.java
index 233b9d41f..bc61ee05f 100644
--- a/src/main/java/de/bixilon/minosoft/data/VersionValueMap.java
+++ b/src/main/java/de/bixilon/minosoft/data/VersionValueMap.java
@@ -13,8 +13,6 @@
 
 package de.bixilon.minosoft.data;
 
-import de.bixilon.minosoft.data.mappings.versions.Versions;
-
 import java.util.Map;
 import java.util.TreeMap;
 
@@ -24,14 +22,14 @@ public class VersionValueMap<V> {
     public VersionValueMap() {
     }
 
-    public VersionValueMap(MapSet<Integer, V>[] sets, boolean unused) {
+    public VersionValueMap(MapSet<Integer, V>[] sets) {
         for (MapSet<Integer, V> set : sets) {
             this.values.put(set.getKey(), set.getValue());
         }
     }
 
-    public VersionValueMap(V value) {
-        this.values.put(Versions.LOWEST_VERSION_SUPPORTED.getVersionId(), value);
+    public VersionValueMap(MapSet<Integer, V> set) {
+        this.values.put(set.getKey(), set.getValue());
     }
 
     public V get(int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/data/entities/EntityMetaData.java b/src/main/java/de/bixilon/minosoft/data/entities/EntityMetaData.java
index 4bb4fdbb8..fdb1deb93 100644
--- a/src/main/java/de/bixilon/minosoft/data/entities/EntityMetaData.java
+++ b/src/main/java/de/bixilon/minosoft/data/entities/EntityMetaData.java
@@ -19,6 +19,7 @@ import de.bixilon.minosoft.data.VersionValueMap;
 import de.bixilon.minosoft.data.inventory.Slot;
 import de.bixilon.minosoft.data.mappings.blocks.Block;
 import de.bixilon.minosoft.data.mappings.particle.data.ParticleData;
+import de.bixilon.minosoft.data.mappings.versions.Versions;
 import de.bixilon.minosoft.data.text.ChatComponent;
 import de.bixilon.minosoft.data.world.BlockPosition;
 import de.bixilon.minosoft.logging.Log;
@@ -118,14 +119,14 @@ public class EntityMetaData {
         OPT_VAR_INT(new MapSet[]{new MapSet<>(459, 17)}),
         POSE(new MapSet[]{new MapSet<>(461, 18)});
 
-        final VersionValueMap<Integer> valueMap;
+        private final VersionValueMap<Integer> valueMap;
 
         EntityMetaDataValueTypes(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         EntityMetaDataValueTypes(int id) {
-            this.valueMap = new VersionValueMap<>(id);
+            this.valueMap = new VersionValueMap<>(new MapSet<>(Versions.LOWEST_VERSION_SUPPORTED.getVersionId(), id));
         }
 
         public static EntityMetaDataValueTypes byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/data/entities/VillagerData.kt b/src/main/java/de/bixilon/minosoft/data/entities/VillagerData.kt
index 0033e4c05..ee0249af4 100644
--- a/src/main/java/de/bixilon/minosoft/data/entities/VillagerData.kt
+++ b/src/main/java/de/bixilon/minosoft/data/entities/VillagerData.kt
@@ -40,7 +40,7 @@ data class VillagerData(val type: VillagerTypes, val profession: VillagerProfess
         ZOMBIE(arrayOf(MapSet(204, -1), MapSet(315, -100)));
 
         // used earlier (ZombieVillagerMeta)
-        private val valueMap = VersionValueMap(values as Array<out MapSet<Int, Int>>, true)
+        private val valueMap = VersionValueMap(values as Array<out MapSet<Int, Int>>)
 
 
         fun getId(versionId: Int): Int {
diff --git a/src/main/java/de/bixilon/minosoft/data/inventory/InventorySlots.java b/src/main/java/de/bixilon/minosoft/data/inventory/InventorySlots.java
index ddd030ce2..84390b811 100644
--- a/src/main/java/de/bixilon/minosoft/data/inventory/InventorySlots.java
+++ b/src/main/java/de/bixilon/minosoft/data/inventory/InventorySlots.java
@@ -15,6 +15,7 @@ package de.bixilon.minosoft.data.inventory;
 
 import de.bixilon.minosoft.data.MapSet;
 import de.bixilon.minosoft.data.VersionValueMap;
+import de.bixilon.minosoft.data.mappings.versions.Versions;
 
 public class InventorySlots {
     public enum PlayerInventorySlots implements InventoryInterface {
@@ -94,11 +95,11 @@ public class InventorySlots {
         final VersionValueMap<Integer> valueMap;
 
         EntityInventorySlots(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         EntityInventorySlots(int id) {
-            this.valueMap = new VersionValueMap<>(id);
+            this.valueMap = new VersionValueMap<>(new MapSet<>(Versions.LOWEST_VERSION_SUPPORTED.getVersionId(), id));
         }
 
         public static EntityInventorySlots byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketBlockEntityMetadata.java b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketBlockEntityMetadata.java
index fceb36ec6..f5201eb5a 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketBlockEntityMetadata.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketBlockEntityMetadata.java
@@ -84,7 +84,7 @@ public class PacketBlockEntityMetadata implements ClientboundPacket {
         final VersionValueMap<Integer> valueMap;
 
         BlockEntityActions(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         public static BlockEntityActions byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketChangeGameState.java b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketChangeGameState.java
index b8662f22c..f7a7f443e 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketChangeGameState.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketChangeGameState.java
@@ -70,7 +70,7 @@ public class PacketChangeGameState implements ClientboundPacket {
         final VersionValueMap<Integer> valueMap;
 
         Reason(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         public static Reason byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEffect.java b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEffect.java
index 90e24480f..5c490ca9e 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEffect.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEffect.java
@@ -150,7 +150,7 @@ public class PacketEffect implements ClientboundPacket {
         final VersionValueMap<Integer> valueMap;
 
         EffectEffects(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         public static EffectEffects byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEntityAnimation.java b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEntityAnimation.java
index 5bb734400..f19bd430f 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEntityAnimation.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketEntityAnimation.java
@@ -57,7 +57,7 @@ public class PacketEntityAnimation implements ClientboundPacket {
         final VersionValueMap<Integer> valueMap;
 
         EntityAnimations(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         public static EntityAnimations byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketTitle.java b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketTitle.java
index 41d44f9df..5cae83bdc 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketTitle.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/packets/clientbound/play/PacketTitle.java
@@ -15,6 +15,7 @@ package de.bixilon.minosoft.protocol.packets.clientbound.play;
 
 import de.bixilon.minosoft.data.MapSet;
 import de.bixilon.minosoft.data.VersionValueMap;
+import de.bixilon.minosoft.data.mappings.versions.Versions;
 import de.bixilon.minosoft.data.text.ChatComponent;
 import de.bixilon.minosoft.logging.Log;
 import de.bixilon.minosoft.protocol.packets.ClientboundPacket;
@@ -93,14 +94,14 @@ public class PacketTitle implements ClientboundPacket {
         HIDE(new MapSet[]{new MapSet<>(18, 3), new MapSet<>(302, 4)}),
         RESET(new MapSet[]{new MapSet<>(18, 4), new MapSet<>(302, 5)});
 
-        final VersionValueMap<Integer> valueMap;
+        private final VersionValueMap<Integer> valueMap;
 
         TitleActions(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         TitleActions(int id) {
-            this.valueMap = new VersionValueMap<>(id);
+            this.valueMap = new VersionValueMap<>(new MapSet<>(Versions.LOWEST_VERSION_SUPPORTED.getVersionId(), id));
         }
 
         public static TitleActions byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/packets/serverbound/play/PacketEntityAction.java b/src/main/java/de/bixilon/minosoft/protocol/packets/serverbound/play/PacketEntityAction.java
index 0e35ce7ed..c32ac1d2b 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/packets/serverbound/play/PacketEntityAction.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/packets/serverbound/play/PacketEntityAction.java
@@ -71,7 +71,7 @@ public class PacketEntityAction implements ServerboundPacket {
         final VersionValueMap<Integer> valueMap;
 
         EntityActions(MapSet<Integer, Integer>[] values) {
-            this.valueMap = new VersionValueMap<>(values, true);
+            this.valueMap = new VersionValueMap<>(values);
         }
 
         public static EntityActions byId(int id, int versionId) {
diff --git a/src/main/java/de/bixilon/minosoft/protocol/protocol/InByteBuffer.java b/src/main/java/de/bixilon/minosoft/protocol/protocol/InByteBuffer.java
index 52298644b..8636ffd19 100644
--- a/src/main/java/de/bixilon/minosoft/protocol/protocol/InByteBuffer.java
+++ b/src/main/java/de/bixilon/minosoft/protocol/protocol/InByteBuffer.java
@@ -248,7 +248,7 @@ public class InByteBuffer {
                 throw new IllegalArgumentException("Bad nbt");
             }
         }
-        TagTypes type = TagTypes.byId(readByte());
+        TagTypes type = TagTypes.byId(readUnsignedByte());
         if (type == TagTypes.COMPOUND) {
             // shouldn't be a subtag
             return new CompoundTag(false, this);
diff --git a/src/main/java/de/bixilon/minosoft/util/BitByte.java b/src/main/java/de/bixilon/minosoft/util/BitByte.java
index 58a634dc2..9e56d12e8 100644
--- a/src/main/java/de/bixilon/minosoft/util/BitByte.java
+++ b/src/main/java/de/bixilon/minosoft/util/BitByte.java
@@ -25,7 +25,7 @@ public final class BitByte {
 
     public static byte getBitCount(int input) {
         byte ret = 0;
-        for (byte i = 0; i < Short.BYTES * 8; i++) { // bytes to bits
+        for (byte i = 0; i < Short.SIZE; i++) {
             if (isBitSet(input, i)) {
                 ret++;
             }
diff --git a/src/main/java/de/bixilon/minosoft/util/nbt/tag/ListTag.java b/src/main/java/de/bixilon/minosoft/util/nbt/tag/ListTag.java
index d9b513e72..30ce34879 100644
--- a/src/main/java/de/bixilon/minosoft/util/nbt/tag/ListTag.java
+++ b/src/main/java/de/bixilon/minosoft/util/nbt/tag/ListTag.java
@@ -20,8 +20,8 @@ import java.util.ArrayList;
 import java.util.Arrays;
 
 public class ListTag extends NBTTag {
-    final TagTypes type;
-    final ArrayList<NBTTag> list;
+    private final TagTypes type;
+    private final ArrayList<NBTTag> list;
 
     public ListTag(TagTypes type, ArrayList<NBTTag> list) {
         this.type = type;
@@ -30,7 +30,7 @@ public class ListTag extends NBTTag {
 
     public ListTag(TagTypes type, NBTTag[] list) {
         this.type = type;
-        this.list = (ArrayList<NBTTag>) Arrays.asList(list);
+        this.list = new ArrayList<>(Arrays.asList(list));
     }
 
     public ListTag(InByteBuffer buffer) {