diff --git a/core/src/main/java/org/geysermc/geyser/entity/type/living/animal/nautilus/AbstractNautilusEntity.java b/core/src/main/java/org/geysermc/geyser/entity/type/living/animal/nautilus/AbstractNautilusEntity.java
index 127335303..317228189 100644
--- a/core/src/main/java/org/geysermc/geyser/entity/type/living/animal/nautilus/AbstractNautilusEntity.java
+++ b/core/src/main/java/org/geysermc/geyser/entity/type/living/animal/nautilus/AbstractNautilusEntity.java
@@ -30,6 +30,7 @@ import org.checkerframework.checker.nullness.qual.Nullable;
 import org.cloudburstmc.math.TrigMath;
 import org.cloudburstmc.math.vector.Vector2f;
 import org.cloudburstmc.math.vector.Vector3f;
+import org.cloudburstmc.protocol.bedrock.data.entity.EntityDataTypes;
 import org.cloudburstmc.protocol.bedrock.data.entity.EntityFlag;
 import org.geysermc.geyser.entity.EntityDefinition;
 import org.geysermc.geyser.entity.type.living.animal.tameable.TameableEntity;
@@ -62,6 +63,8 @@ public abstract class AbstractNautilusEntity extends TameableEntity implements C
     public AbstractNautilusEntity(GeyserSession session, int entityId, long geyserId, UUID uuid, EntityDefinition<?> definition, Vector3f position, Vector3f motion, float yaw, float pitch, float headYaw, float defSpeed) {
         super(session, entityId, geyserId, uuid, definition, position, motion, yaw, pitch, headYaw);
         this.vehicleComponent = new NautilusVehicleComponent(this, 0.0f, defSpeed);
+
+        dirtyMetadata.put(EntityDataTypes.CONTAINER_SIZE, 2);
     }
 
     @Override
diff --git a/core/src/main/java/org/geysermc/geyser/inventory/updater/HorseInventoryUpdater.java b/core/src/main/java/org/geysermc/geyser/inventory/updater/MountInventoryUpdater.java
similarity index 93%
rename from core/src/main/java/org/geysermc/geyser/inventory/updater/HorseInventoryUpdater.java
rename to core/src/main/java/org/geysermc/geyser/inventory/updater/MountInventoryUpdater.java
index 2f2c79ebf..0798295e4 100644
--- a/core/src/main/java/org/geysermc/geyser/inventory/updater/HorseInventoryUpdater.java
+++ b/core/src/main/java/org/geysermc/geyser/inventory/updater/MountInventoryUpdater.java
@@ -34,8 +34,8 @@ import org.geysermc.geyser.translator.inventory.InventoryTranslator;
 
 import java.util.Arrays;
 
-public class HorseInventoryUpdater extends InventoryUpdater {
-    public static final HorseInventoryUpdater INSTANCE = new HorseInventoryUpdater();
+public class MountInventoryUpdater extends InventoryUpdater {
+    public static final MountInventoryUpdater INSTANCE = new MountInventoryUpdater();
 
     @Override
     public void updateInventory(InventoryTranslator<?> translator, GeyserSession session, Inventory inventory) {
@@ -58,10 +58,11 @@ public class HorseInventoryUpdater extends InventoryUpdater {
             return true;
 
         InventorySlotPacket slotPacket = new InventorySlotPacket();
-        slotPacket.setContainerId(4); // Horse GUI?
+        slotPacket.setContainerId(inventory.getBedrockId());
         slotPacket.setSlot(translator.javaSlotToBedrock(javaSlot));
         slotPacket.setItem(inventory.getItem(javaSlot).getItemData(session));
         session.sendUpstreamPacket(slotPacket);
+
         return true;
     }
 }
diff --git a/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/AbstractHorseInventoryTranslator.java b/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/AbstractMountInventoryTranslator.java
similarity index 90%
rename from core/src/main/java/org/geysermc/geyser/translator/inventory/horse/AbstractHorseInventoryTranslator.java
rename to core/src/main/java/org/geysermc/geyser/translator/inventory/horse/AbstractMountInventoryTranslator.java
index 9c56503c1..b77f1a2ac 100644
--- a/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/AbstractHorseInventoryTranslator.java
+++ b/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/AbstractMountInventoryTranslator.java
@@ -26,17 +26,17 @@
 package org.geysermc.geyser.translator.inventory.horse;
 
 import org.geysermc.geyser.inventory.Container;
-import org.geysermc.geyser.inventory.updater.HorseInventoryUpdater;
+import org.geysermc.geyser.inventory.updater.MountInventoryUpdater;
 import org.geysermc.geyser.inventory.updater.InventoryUpdater;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.inventory.BaseInventoryTranslator;
 
-public abstract class AbstractHorseInventoryTranslator extends BaseInventoryTranslator<Container> {
+public abstract class AbstractMountInventoryTranslator extends BaseInventoryTranslator<Container> {
     private final InventoryUpdater updater;
 
-    public AbstractHorseInventoryTranslator(int size) {
+    public AbstractMountInventoryTranslator(int size) {
         super(size);
-        this.updater = HorseInventoryUpdater.INSTANCE;
+        this.updater = MountInventoryUpdater.INSTANCE;
     }
 
     @Override
diff --git a/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/ChestedHorseInventoryTranslator.java b/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/ChestedHorseInventoryTranslator.java
index 50d977d75..255fcc001 100644
--- a/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/ChestedHorseInventoryTranslator.java
+++ b/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/ChestedHorseInventoryTranslator.java
@@ -36,7 +36,7 @@ import org.geysermc.geyser.session.GeyserSession;
 
 import java.util.Arrays;
 
-public abstract class ChestedHorseInventoryTranslator extends AbstractHorseInventoryTranslator {
+public abstract class ChestedHorseInventoryTranslator extends AbstractMountInventoryTranslator {
     private final int chestSize;
     private final int equipSlot;
 
diff --git a/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/HorseInventoryTranslator.java b/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/MountInventoryTranslator.java
similarity index 95%
rename from core/src/main/java/org/geysermc/geyser/translator/inventory/horse/HorseInventoryTranslator.java
rename to core/src/main/java/org/geysermc/geyser/translator/inventory/horse/MountInventoryTranslator.java
index 976c49f48..69ccf3cdb 100644
--- a/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/HorseInventoryTranslator.java
+++ b/core/src/main/java/org/geysermc/geyser/translator/inventory/horse/MountInventoryTranslator.java
@@ -30,8 +30,8 @@ import org.cloudburstmc.protocol.bedrock.data.inventory.itemstack.request.ItemSt
 import org.geysermc.geyser.inventory.BedrockContainerSlot;
 import org.geysermc.geyser.inventory.Container;
 
-public class HorseInventoryTranslator extends AbstractHorseInventoryTranslator {
-    public HorseInventoryTranslator(int size) {
+public class MountInventoryTranslator extends AbstractMountInventoryTranslator {
+    public MountInventoryTranslator(int size) {
         super(size);
     }
 
diff --git a/core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockInteractTranslator.java b/core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockInteractTranslator.java
index dab08d090..7a430cd55 100644
--- a/core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockInteractTranslator.java
+++ b/core/src/main/java/org/geysermc/geyser/translator/protocol/bedrock/entity/player/BedrockInteractTranslator.java
@@ -32,6 +32,7 @@ import org.cloudburstmc.protocol.bedrock.packet.SetEntityLinkPacket;
 import org.geysermc.geyser.entity.type.ChestBoatEntity;
 import org.geysermc.geyser.entity.type.Entity;
 import org.geysermc.geyser.entity.type.living.animal.horse.AbstractHorseEntity;
+import org.geysermc.geyser.entity.type.living.animal.nautilus.AbstractNautilusEntity;
 import org.geysermc.geyser.item.Items;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.protocol.PacketTranslator;
@@ -122,7 +123,7 @@ public class BedrockInteractTranslator extends PacketTranslator<InteractPacket>
             case OPEN_INVENTORY:
                 if (session.getInventoryHolder() == null) {
                     Entity ridingEntity = session.getPlayerEntity().getVehicle();
-                    if (ridingEntity instanceof AbstractHorseEntity || ridingEntity instanceof ChestBoatEntity) {
+                    if (ridingEntity instanceof AbstractHorseEntity || ridingEntity instanceof AbstractNautilusEntity || ridingEntity instanceof ChestBoatEntity) {
                         // This mob has an inventory of its own that we should open instead.
                         ServerboundPlayerCommandPacket openVehicleWindowPacket = new ServerboundPlayerCommandPacket(session.getPlayerEntity().getEntityId(), PlayerState.OPEN_VEHICLE_INVENTORY);
                         session.sendDownstreamGamePacket(openVehicleWindowPacket);
diff --git a/core/src/main/java/org/geysermc/geyser/translator/protocol/java/inventory/JavaHorseScreenOpenTranslator.java b/core/src/main/java/org/geysermc/geyser/translator/protocol/java/inventory/JavaMountScreenOpenTranslator.java
similarity index 78%
rename from core/src/main/java/org/geysermc/geyser/translator/protocol/java/inventory/JavaHorseScreenOpenTranslator.java
rename to core/src/main/java/org/geysermc/geyser/translator/protocol/java/inventory/JavaMountScreenOpenTranslator.java
index 77c1383a5..78ec3a203 100644
--- a/core/src/main/java/org/geysermc/geyser/translator/protocol/java/inventory/JavaHorseScreenOpenTranslator.java
+++ b/core/src/main/java/org/geysermc/geyser/translator/protocol/java/inventory/JavaMountScreenOpenTranslator.java
@@ -37,12 +37,13 @@ import org.geysermc.geyser.entity.type.living.animal.horse.ChestedHorseEntity;
 import org.geysermc.geyser.entity.type.living.animal.horse.LlamaEntity;
 import org.geysermc.geyser.entity.type.living.animal.horse.SkeletonHorseEntity;
 import org.geysermc.geyser.entity.type.living.animal.horse.ZombieHorseEntity;
+import org.geysermc.geyser.entity.type.living.animal.nautilus.NautilusEntity;
 import org.geysermc.geyser.inventory.Container;
 import org.geysermc.geyser.inventory.InventoryHolder;
 import org.geysermc.geyser.session.GeyserSession;
 import org.geysermc.geyser.translator.inventory.InventoryTranslator;
 import org.geysermc.geyser.translator.inventory.horse.DonkeyInventoryTranslator;
-import org.geysermc.geyser.translator.inventory.horse.HorseInventoryTranslator;
+import org.geysermc.geyser.translator.inventory.horse.MountInventoryTranslator;
 import org.geysermc.geyser.translator.inventory.horse.LlamaInventoryTranslator;
 import org.geysermc.geyser.translator.protocol.PacketTranslator;
 import org.geysermc.geyser.translator.protocol.Translator;
@@ -54,36 +55,24 @@ import java.util.Collections;
 import java.util.List;
 
 @Translator(packet = ClientboundMountScreenOpenPacket.class)
-public class JavaHorseScreenOpenTranslator extends PacketTranslator<ClientboundMountScreenOpenPacket> {
+public class JavaMountScreenOpenTranslator extends PacketTranslator<ClientboundMountScreenOpenPacket> {
+    private static final String[] ACCEPTED_HORSE_ARMORS = new String[] {"minecraft:horsearmorleather", "minecraft:horsearmoriron",
+        "minecraft:horsearmorgold", "minecraft:horsearmordiamond", "minecraft:copper_horse_armor", "minecraft:netherite_horse_armor"};
+    private static final String[] ACCEPTED_NAUTILUS_ARMORS = new String[] {"minecraft:copper_nautilus_armor", "minecraft:iron_nautilus_armor",
+        "minecraft:golden_nautilus_armor", "minecraft:diamond_nautilus_armor", "minecraft:netherite_nautilus_armor"};
 
-    private static final NbtMap ARMOR_SLOT;
-    private static final NbtMap CARPET_SLOT;
-    private static final NbtMap SADDLE_SLOT;
+
+    private static final NbtMap SADDLE_SLOT, CARPET_SLOT;
+    private static final NbtMap HORSE_ARMOR_SLOT, NAUTILUS_ARMOR_SLOT;
 
     static {
-        // Build the NBT mappings that Bedrock wants to lay out the GUI
-        String[] acceptedHorseArmorIdentifiers = new String[] {"minecraft:horsearmorleather", "minecraft:horsearmoriron",
-                "minecraft:horsearmorgold", "minecraft:horsearmordiamond"};
-        NbtMapBuilder armorBuilder = NbtMap.builder();
-        List<NbtMap> acceptedArmors = new ArrayList<>(4);
-        for (String identifier : acceptedHorseArmorIdentifiers) {
-            NbtMapBuilder acceptedItemBuilder = NbtMap.builder()
-                    .putShort("Aux", Short.MAX_VALUE)
-                    .putString("Name", identifier);
-            acceptedArmors.add(NbtMap.builder().putCompound("slotItem", acceptedItemBuilder.build()).build());
-        }
-        armorBuilder.putList("acceptedItems", NbtType.COMPOUND, acceptedArmors);
-        NbtMapBuilder armorItem = NbtMap.builder()
-                .putShort("Aux", Short.MAX_VALUE)
-                .putString("Name", "minecraft:horsearmoriron");
-        armorBuilder.putCompound("item", armorItem.build());
-        armorBuilder.putInt("slotNumber", 1);
-        ARMOR_SLOT = armorBuilder.build();
+        HORSE_ARMOR_SLOT = buildAcceptedArmorSlot(ACCEPTED_HORSE_ARMORS, "minecraft:horsearmoriron");
+        NAUTILUS_ARMOR_SLOT = buildAcceptedArmorSlot(ACCEPTED_NAUTILUS_ARMORS, "minecraft:nautilusarmor");
 
         NbtMapBuilder carpetBuilder = NbtMap.builder();
         NbtMapBuilder carpetItem = NbtMap.builder()
-                .putShort("Aux", Short.MAX_VALUE)
-                .putString("Name", "minecraft:carpet");
+            .putShort("Aux", Short.MAX_VALUE)
+            .putString("Name", "minecraft:carpet");
         List<NbtMap> acceptedCarpet = Collections.singletonList(NbtMap.builder().putCompound("slotItem", carpetItem.build()).build());
         carpetBuilder.putList("acceptedItems", NbtType.COMPOUND, acceptedCarpet);
         carpetBuilder.putCompound("item", carpetItem.build());
@@ -92,8 +81,8 @@ public class JavaHorseScreenOpenTranslator extends PacketTranslator<ClientboundM
 
         NbtMapBuilder saddleBuilder = NbtMap.builder();
         NbtMapBuilder acceptedSaddle = NbtMap.builder()
-                .putShort("Aux", Short.MAX_VALUE)
-                .putString("Name", "minecraft:saddle");
+            .putShort("Aux", Short.MAX_VALUE)
+            .putString("Name", "minecraft:saddle");
         List<NbtMap> acceptedItem = Collections.singletonList(NbtMap.builder().putCompound("slotItem", acceptedSaddle.build()).build());
         saddleBuilder.putList("acceptedItems", NbtType.COMPOUND, acceptedItem);
         saddleBuilder.putCompound("item", acceptedSaddle.build());
@@ -101,6 +90,26 @@ public class JavaHorseScreenOpenTranslator extends PacketTranslator<ClientboundM
         SADDLE_SLOT = saddleBuilder.build();
     }
 
+    private static NbtMap buildAcceptedArmorSlot(String[] accepted, String name) {
+        NbtMapBuilder armorBuilder = NbtMap.builder();
+        List<NbtMap> acceptedArmors = new ArrayList<>(4);
+
+        for (String identifier : accepted) {
+            NbtMapBuilder acceptedItemBuilder = NbtMap.builder()
+                .putShort("Aux", Short.MAX_VALUE)
+                .putString("Name", identifier);
+            acceptedArmors.add(NbtMap.builder().putCompound("slotItem", acceptedItemBuilder.build()).build());
+        }
+
+        armorBuilder.putList("acceptedItems", NbtType.COMPOUND, acceptedArmors);
+        NbtMapBuilder armorItem = NbtMap.builder()
+            .putShort("Aux", Short.MAX_VALUE)
+            .putString("Name", name);
+        armorBuilder.putCompound("item", armorItem.build());
+        armorBuilder.putInt("slotNumber", 1);
+        return armorBuilder.build();
+    }
+
     @Override
     public void translate(GeyserSession session, ClientboundMountScreenOpenPacket packet) {
         Entity entity = session.getEntityCache().getEntityByJavaId(packet.getEntityId());
@@ -141,10 +150,12 @@ public class JavaHorseScreenOpenTranslator extends PacketTranslator<ClientboundM
             inventoryTranslator = new DonkeyInventoryTranslator(slotCount);
             slots.add(SADDLE_SLOT);
         } else {
-            inventoryTranslator = new HorseInventoryTranslator(slotCount);
+            inventoryTranslator = new MountInventoryTranslator(slotCount);
             slots.add(SADDLE_SLOT);
-            if (!(entity instanceof SkeletonHorseEntity || entity instanceof ZombieHorseEntity)) {
-                slots.add(ARMOR_SLOT);
+            if (entity instanceof NautilusEntity) {
+                slots.add(NAUTILUS_ARMOR_SLOT);
+            } else if (!(entity instanceof SkeletonHorseEntity || entity instanceof ZombieHorseEntity)) {
+                slots.add(HORSE_ARMOR_SLOT);
             }
         }