diff --git a/protocol/build.gradle.kts b/protocol/build.gradle.kts
index 09bb99206..3de44b97a 100644
--- a/protocol/build.gradle.kts
+++ b/protocol/build.gradle.kts
@@ -5,7 +5,7 @@ plugins {
     jacoco
 }
 
-version = "26.1-SNAPSHOT"
+version = "26.1-feature-custom-entities-SNAPSHOT"
 description = "MCProtocolLib is a simple library for communicating with Minecraft clients and servers."
 
 dependencies {
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/BuiltinEntityType.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/BuiltinEntityType.java
new file mode 100644
index 000000000..fd2dd8781
--- /dev/null
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/BuiltinEntityType.java
@@ -0,0 +1,181 @@
+package org.geysermc.mcprotocollib.protocol.data.game.entity.type;
+
+import lombok.Getter;
+
+public enum BuiltinEntityType implements EntityType {
+    ACACIA_BOAT,
+    ACACIA_CHEST_BOAT,
+    ALLAY,
+    AREA_EFFECT_CLOUD,
+    ARMADILLO,
+    ARMOR_STAND,
+    ARROW(true),
+    AXOLOTL,
+    BAMBOO_CHEST_RAFT,
+    BAMBOO_RAFT,
+    BAT,
+    BEE,
+    BIRCH_BOAT,
+    BIRCH_CHEST_BOAT,
+    BLAZE,
+    BLOCK_DISPLAY,
+    BOGGED,
+    BREEZE,
+    BREEZE_WIND_CHARGE(true),
+    CAMEL,
+    CAMEL_HUSK,
+    CAT,
+    CAVE_SPIDER,
+    CHERRY_BOAT,
+    CHERRY_CHEST_BOAT,
+    CHEST_MINECART,
+    CHICKEN,
+    COD,
+    COPPER_GOLEM,
+    COMMAND_BLOCK_MINECART,
+    COW,
+    CREAKING,
+    CREEPER,
+    DARK_OAK_BOAT,
+    DARK_OAK_CHEST_BOAT,
+    DOLPHIN,
+    DONKEY,
+    DRAGON_FIREBALL(true),
+    DROWNED,
+    EGG(true),
+    ELDER_GUARDIAN,
+    ENDERMAN,
+    ENDERMITE,
+    ENDER_DRAGON,
+    ENDER_PEARL(true),
+    END_CRYSTAL,
+    EVOKER,
+    EVOKER_FANGS,
+    EXPERIENCE_BOTTLE(true),
+    EXPERIENCE_ORB,
+    EYE_OF_ENDER,
+    FALLING_BLOCK,
+    FIREBALL(true),
+    FIREWORK_ROCKET(true),
+    FOX,
+    FROG,
+    FURNACE_MINECART,
+    GHAST,
+    HAPPY_GHAST,
+    GIANT,
+    GLOW_ITEM_FRAME,
+    GLOW_SQUID,
+    GOAT,
+    GUARDIAN,
+    HOGLIN,
+    HOPPER_MINECART,
+    HORSE,
+    HUSK,
+    ILLUSIONER,
+    INTERACTION,
+    IRON_GOLEM,
+    ITEM,
+    ITEM_DISPLAY,
+    ITEM_FRAME,
+    JUNGLE_BOAT,
+    JUNGLE_CHEST_BOAT,
+    LEASH_KNOT,
+    LIGHTNING_BOLT,
+    LLAMA,
+    LLAMA_SPIT(true),
+    MAGMA_CUBE,
+    MANGROVE_BOAT,
+    MANGROVE_CHEST_BOAT,
+    MANNEQUIN,
+    MARKER,
+    MINECART,
+    MOOSHROOM,
+    MULE,
+    NAUTILUS,
+    OAK_BOAT,
+    OAK_CHEST_BOAT,
+    OCELOT,
+    OMINOUS_ITEM_SPAWNER,
+    PAINTING,
+    PALE_OAK_BOAT,
+    PALE_OAK_CHEST_BOAT,
+    PANDA,
+    PARCHED,
+    PARROT,
+    PHANTOM,
+    PIG,
+    PIGLIN,
+    PIGLIN_BRUTE,
+    PILLAGER,
+    POLAR_BEAR,
+    SPLASH_POTION(true),
+    LINGERING_POTION(true),
+    PUFFERFISH,
+    RABBIT,
+    RAVAGER,
+    SALMON,
+    SHEEP,
+    SHULKER,
+    SHULKER_BULLET(true),
+    SILVERFISH,
+    SKELETON,
+    SKELETON_HORSE,
+    SLIME,
+    SMALL_FIREBALL(true),
+    SNIFFER,
+    SNOWBALL(true),
+    SNOW_GOLEM,
+    SPAWNER_MINECART,
+    SPECTRAL_ARROW(true),
+    SPIDER,
+    SPRUCE_BOAT,
+    SPRUCE_CHEST_BOAT,
+    SQUID,
+    STRAY,
+    STRIDER,
+    TADPOLE,
+    TEXT_DISPLAY,
+    TNT,
+    TNT_MINECART,
+    TRADER_LLAMA,
+    TRIDENT(true),
+    TROPICAL_FISH,
+    TURTLE,
+    VEX,
+    VILLAGER,
+    VINDICATOR,
+    WANDERING_TRADER,
+    WARDEN,
+    WIND_CHARGE(true),
+    WITCH,
+    WITHER,
+    WITHER_SKELETON,
+    WITHER_SKULL(true),
+    WOLF,
+    ZOGLIN,
+    ZOMBIE,
+    ZOMBIE_HORSE,
+    ZOMBIE_NAUTILUS,
+    ZOMBIE_VILLAGER,
+    ZOMBIFIED_PIGLIN,
+    PLAYER,
+    FISHING_BOBBER(true);
+
+    @Getter
+    private final boolean projectile;
+
+    BuiltinEntityType() {
+        this.projectile = false;
+    }
+
+    BuiltinEntityType(boolean projectile) {
+        this.projectile = projectile;
+    }
+
+    public static final BuiltinEntityType[] VALUES = values();
+
+    @Override
+    public int id() {
+        return ordinal();
+    }
+}
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/BuiltinPaintingType.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/BuiltinPaintingType.java
new file mode 100644
index 000000000..9dfec884c
--- /dev/null
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/BuiltinPaintingType.java
@@ -0,0 +1,61 @@
+package org.geysermc.mcprotocollib.protocol.data.game.entity.type;
+
+public enum BuiltinPaintingType implements PaintingType {
+    KEBAB,
+    AZTEC,
+    ALBAN,
+    AZTEC2,
+    BOMB,
+    PLANT,
+    WASTELAND,
+    POOL,
+    COURBET,
+    SEA,
+    SUNSET,
+    CREEBET,
+    WANDERER,
+    GRAHAM,
+    MATCH,
+    BUST,
+    STAGE,
+    VOID,
+    SKULL_AND_ROSES,
+    WITHER,
+    FIGHTERS,
+    POINTER,
+    PIGSCENE,
+    BURNING_SKULL,
+    SKELETON,
+    EARTH,
+    WIND,
+    WATER,
+    FIRE,
+    DONKEY_KONG,
+    BAROQUE,
+    HUMBLE,
+    MEDITATIVE,
+    PRAIRIE_RIDE,
+    UNPACKED,
+    BACKYARD,
+    BOUQUET,
+    CAVEBIRD,
+    CHANGING,
+    COTAN,
+    ENDBOSS,
+    FERN,
+    FINDING,
+    LOWMIST,
+    ORB,
+    OWLEMONS,
+    PASSAGE,
+    POND,
+    SUNFLOWERS,
+    TIDES;
+
+    public static final BuiltinPaintingType[] VALUES = values();
+
+    @Override
+    public int id() {
+        return ordinal();
+    }
+}
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/EntityType.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/EntityType.java
index ef5df4f1d..68edf3645 100644
--- a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/EntityType.java
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/EntityType.java
@@ -1,180 +1,26 @@
 package org.geysermc.mcprotocollib.protocol.data.game.entity.type;
 
-import lombok.Getter;
+public interface EntityType {
 
-public enum EntityType {
-    ACACIA_BOAT,
-    ACACIA_CHEST_BOAT,
-    ALLAY,
-    AREA_EFFECT_CLOUD,
-    ARMADILLO,
-    ARMOR_STAND,
-    ARROW(true),
-    AXOLOTL,
-    BAMBOO_CHEST_RAFT,
-    BAMBOO_RAFT,
-    BAT,
-    BEE,
-    BIRCH_BOAT,
-    BIRCH_CHEST_BOAT,
-    BLAZE,
-    BLOCK_DISPLAY,
-    BOGGED,
-    BREEZE,
-    BREEZE_WIND_CHARGE(true),
-    CAMEL,
-    CAMEL_HUSK,
-    CAT,
-    CAVE_SPIDER,
-    CHERRY_BOAT,
-    CHERRY_CHEST_BOAT,
-    CHEST_MINECART,
-    CHICKEN,
-    COD,
-    COPPER_GOLEM,
-    COMMAND_BLOCK_MINECART,
-    COW,
-    CREAKING,
-    CREEPER,
-    DARK_OAK_BOAT,
-    DARK_OAK_CHEST_BOAT,
-    DOLPHIN,
-    DONKEY,
-    DRAGON_FIREBALL(true),
-    DROWNED,
-    EGG(true),
-    ELDER_GUARDIAN,
-    ENDERMAN,
-    ENDERMITE,
-    ENDER_DRAGON,
-    ENDER_PEARL(true),
-    END_CRYSTAL,
-    EVOKER,
-    EVOKER_FANGS,
-    EXPERIENCE_BOTTLE(true),
-    EXPERIENCE_ORB,
-    EYE_OF_ENDER,
-    FALLING_BLOCK,
-    FIREBALL(true),
-    FIREWORK_ROCKET(true),
-    FOX,
-    FROG,
-    FURNACE_MINECART,
-    GHAST,
-    HAPPY_GHAST,
-    GIANT,
-    GLOW_ITEM_FRAME,
-    GLOW_SQUID,
-    GOAT,
-    GUARDIAN,
-    HOGLIN,
-    HOPPER_MINECART,
-    HORSE,
-    HUSK,
-    ILLUSIONER,
-    INTERACTION,
-    IRON_GOLEM,
-    ITEM,
-    ITEM_DISPLAY,
-    ITEM_FRAME,
-    JUNGLE_BOAT,
-    JUNGLE_CHEST_BOAT,
-    LEASH_KNOT,
-    LIGHTNING_BOLT,
-    LLAMA,
-    LLAMA_SPIT(true),
-    MAGMA_CUBE,
-    MANGROVE_BOAT,
-    MANGROVE_CHEST_BOAT,
-    MANNEQUIN,
-    MARKER,
-    MINECART,
-    MOOSHROOM,
-    MULE,
-    NAUTILUS,
-    OAK_BOAT,
-    OAK_CHEST_BOAT,
-    OCELOT,
-    OMINOUS_ITEM_SPAWNER,
-    PAINTING,
-    PALE_OAK_BOAT,
-    PALE_OAK_CHEST_BOAT,
-    PANDA,
-    PARCHED,
-    PARROT,
-    PHANTOM,
-    PIG,
-    PIGLIN,
-    PIGLIN_BRUTE,
-    PILLAGER,
-    POLAR_BEAR,
-    SPLASH_POTION(true),
-    LINGERING_POTION(true),
-    PUFFERFISH,
-    RABBIT,
-    RAVAGER,
-    SALMON,
-    SHEEP,
-    SHULKER,
-    SHULKER_BULLET(true),
-    SILVERFISH,
-    SKELETON,
-    SKELETON_HORSE,
-    SLIME,
-    SMALL_FIREBALL(true),
-    SNIFFER,
-    SNOWBALL(true),
-    SNOW_GOLEM,
-    SPAWNER_MINECART,
-    SPECTRAL_ARROW(true),
-    SPIDER,
-    SPRUCE_BOAT,
-    SPRUCE_CHEST_BOAT,
-    SQUID,
-    STRAY,
-    STRIDER,
-    TADPOLE,
-    TEXT_DISPLAY,
-    TNT,
-    TNT_MINECART,
-    TRADER_LLAMA,
-    TRIDENT(true),
-    TROPICAL_FISH,
-    TURTLE,
-    VEX,
-    VILLAGER,
-    VINDICATOR,
-    WANDERING_TRADER,
-    WARDEN,
-    WIND_CHARGE(true),
-    WITCH,
-    WITHER,
-    WITHER_SKELETON,
-    WITHER_SKULL(true),
-    WOLF,
-    ZOGLIN,
-    ZOMBIE,
-    ZOMBIE_HORSE,
-    ZOMBIE_NAUTILUS,
-    ZOMBIE_VILLAGER,
-    ZOMBIFIED_PIGLIN,
-    PLAYER,
-    FISHING_BOBBER(true);
+    int id();
 
-    @Getter
-    private final boolean projectile;
+    boolean isProjectile();
 
-    EntityType() {
-        this.projectile = false;
+    static EntityType from(int id) {
+        if (id < 0 || id >= BuiltinEntityType.VALUES.length) {
+            return new Custom(id);
+        }
+        return BuiltinEntityType.VALUES[id];
     }
 
-    EntityType(boolean projectile) {
-        this.projectile = projectile;
+    default boolean is(EntityType type) {
+        return id() == type.id();
     }
 
-    private static final EntityType[] VALUES = values();
-
-    public static EntityType from(int id) {
-        return VALUES[id];
+    record Custom(int id) implements EntityType {
+        @Override
+        public boolean isProjectile() {
+            return false;
+        }
     }
 }
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/PaintingType.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/PaintingType.java
index fa86e9355..b8e750503 100644
--- a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/PaintingType.java
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/entity/type/PaintingType.java
@@ -1,60 +1,16 @@
 package org.geysermc.mcprotocollib.protocol.data.game.entity.type;
 
-public enum PaintingType {
-    KEBAB,
-    AZTEC,
-    ALBAN,
-    AZTEC2,
-    BOMB,
-    PLANT,
-    WASTELAND,
-    POOL,
-    COURBET,
-    SEA,
-    SUNSET,
-    CREEBET,
-    WANDERER,
-    GRAHAM,
-    MATCH,
-    BUST,
-    STAGE,
-    VOID,
-    SKULL_AND_ROSES,
-    WITHER,
-    FIGHTERS,
-    POINTER,
-    PIGSCENE,
-    BURNING_SKULL,
-    SKELETON,
-    EARTH,
-    WIND,
-    WATER,
-    FIRE,
-    DONKEY_KONG,
-    BAROQUE,
-    HUMBLE,
-    MEDITATIVE,
-    PRAIRIE_RIDE,
-    UNPACKED,
-    BACKYARD,
-    BOUQUET,
-    CAVEBIRD,
-    CHANGING,
-    COTAN,
-    ENDBOSS,
-    FERN,
-    FINDING,
-    LOWMIST,
-    ORB,
-    OWLEMONS,
-    PASSAGE,
-    POND,
-    SUNFLOWERS,
-    TIDES;
+public interface PaintingType {
 
-    private static final PaintingType[] VALUES = values();
+    int id();
 
-    public static PaintingType from(int id) {
-        return VALUES[id];
+    static PaintingType from(int id) {
+        if (id < 0 || id >= BuiltinPaintingType.values().length) {
+            return new Custom(id);
+        }
+        return BuiltinPaintingType.VALUES[id];
+    }
+
+    record Custom(int id) implements PaintingType {
     }
 }
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/ItemTypes.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/ItemTypes.java
index 6b4946e24..d34ccf3c9 100644
--- a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/ItemTypes.java
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/data/game/item/component/ItemTypes.java
@@ -623,7 +623,7 @@ public static void writeTrimPattern(ByteBuf buf, ArmorTrim.TrimPattern pattern)
         buf.writeBoolean(pattern.decal());
     }
 
-    public static <T extends Enum<?>> TypedEntityData<T> readTypedEntityData(ByteBuf buf, Function<ByteBuf, T> reader) {
+    public static <T> TypedEntityData<T> readTypedEntityData(ByteBuf buf, Function<ByteBuf, T> reader) {
         return new TypedEntityData<>(reader.apply(buf), MinecraftTypes.readCompoundTag(buf));
     }
 
@@ -637,7 +637,7 @@ public static EntityType readEntityType(ByteBuf buf) {
     }
 
     public static void writeEntityType(ByteBuf buf, EntityType state) {
-        MinecraftTypes.writeVarInt(buf, state.ordinal());
+        MinecraftTypes.writeVarInt(buf, state.id());
     }
 
     public static BlockEntityType readBlockEntityType(ByteBuf buf) {
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundAwardStatsPacket.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundAwardStatsPacket.java
index cb25cd1c5..1b3f25aa2 100644
--- a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundAwardStatsPacket.java
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/ClientboundAwardStatsPacket.java
@@ -76,10 +76,10 @@ public void serialize(ByteBuf out) {
                 statisticId = ((DropItemStatistic) statistic).getId();
             } else if (statistic instanceof KillEntityStatistic) {
                 category = StatisticCategory.KILL_ENTITY;
-                statisticId = ((KillEntityStatistic) statistic).getEntity().ordinal();
+                statisticId = ((KillEntityStatistic) statistic).getEntity().id();
             } else if (statistic instanceof KilledByEntityStatistic) {
                 category = StatisticCategory.KILLED_BY_ENTITY;
-                statisticId = ((KilledByEntityStatistic) statistic).getEntity().ordinal();
+                statisticId = ((KilledByEntityStatistic) statistic).getEntity().id();
             } else if (statistic instanceof CustomStatistic) {
                 category = StatisticCategory.CUSTOM;
                 statisticId = ((CustomStatistic) statistic).ordinal();
diff --git a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/entity/ClientboundAddEntityPacket.java b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/entity/ClientboundAddEntityPacket.java
index bc17d3e1d..48fb8249f 100644
--- a/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/entity/ClientboundAddEntityPacket.java
+++ b/protocol/src/main/java/org/geysermc/mcprotocollib/protocol/packet/ingame/clientbound/entity/ClientboundAddEntityPacket.java
@@ -15,6 +15,7 @@
 import org.geysermc.mcprotocollib.protocol.data.game.entity.object.ObjectData;
 import org.geysermc.mcprotocollib.protocol.data.game.entity.object.ProjectileData;
 import org.geysermc.mcprotocollib.protocol.data.game.entity.object.WardenData;
+import org.geysermc.mcprotocollib.protocol.data.game.entity.type.BuiltinEntityType;
 import org.geysermc.mcprotocollib.protocol.data.game.entity.type.EntityType;
 
 import java.util.UUID;
@@ -66,15 +67,15 @@ public ClientboundAddEntityPacket(ByteBuf in) {
         this.headYaw = in.readByte() * 360 / 256f;
 
         int data = MinecraftTypes.readVarInt(in);
-        if (this.type == EntityType.MINECART) {
+        if (this.type == BuiltinEntityType.MINECART) {
             this.data = MinecartType.from(data);
-        } else if (this.type == EntityType.ITEM_FRAME || this.type == EntityType.GLOW_ITEM_FRAME || this.type == EntityType.PAINTING) {
+        } else if (this.type == BuiltinEntityType.ITEM_FRAME || this.type == BuiltinEntityType.GLOW_ITEM_FRAME || this.type == BuiltinEntityType.PAINTING) {
             this.data = Direction.VALUES[data];
-        } else if (this.type == EntityType.FALLING_BLOCK) {
+        } else if (this.type == BuiltinEntityType.FALLING_BLOCK) {
             this.data = new FallingBlockData(data & 65535, data >> 16);
-        } else if (this.type.isProjectile()) {
+        } else if (type.isProjectile()) {
             this.data = new ProjectileData(data);
-        } else if (this.type == EntityType.WARDEN) {
+        } else if (this.type == BuiltinEntityType.WARDEN) {
             this.data = new WardenData(data);
         } else {
             if (data == 0) {
@@ -89,7 +90,7 @@ public ClientboundAddEntityPacket(ByteBuf in) {
     public void serialize(ByteBuf out) {
         MinecraftTypes.writeVarInt(out, this.entityId);
         MinecraftTypes.writeUUID(out, this.uuid);
-        MinecraftTypes.writeVarInt(out, this.type.ordinal());
+        MinecraftTypes.writeVarInt(out, this.type.id());
         out.writeDouble(this.x);
         out.writeDouble(this.y);
         out.writeDouble(this.z);