diff --git a/projects/common/src/client/java/dan200/computercraft/client/render/TurtleBlockEntityRenderer.java b/projects/common/src/client/java/dan200/computercraft/client/render/TurtleBlockEntityRenderer.java
index 92fce737f..c52c5a485 100644
--- a/projects/common/src/client/java/dan200/computercraft/client/render/TurtleBlockEntityRenderer.java
+++ b/projects/common/src/client/java/dan200/computercraft/client/render/TurtleBlockEntityRenderer.java
@@ -11,7 +11,6 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.client.platform.ClientPlatformHelper;
 import dan200.computercraft.client.turtle.TurtleUpgradeModellers;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.turtle.blocks.TurtleBlockEntity;
 import dan200.computercraft.shared.util.Holiday;
 import net.minecraft.client.Minecraft;
@@ -21,7 +20,6 @@ import net.minecraft.client.renderer.blockentity.BlockEntityRenderDispatcher;
 import net.minecraft.client.renderer.blockentity.BlockEntityRenderer;
 import net.minecraft.client.renderer.blockentity.BlockEntityRendererProvider;
 import net.minecraft.client.resources.model.BakedModel;
-import net.minecraft.client.resources.model.ModelResourceLocation;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.phys.BlockHitResult;
 import net.minecraft.world.phys.HitResult;
@@ -29,8 +27,6 @@ import net.minecraft.world.phys.HitResult;
 import javax.annotation.Nullable;
 
 public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBlockEntity> {
-    private static final ModelResourceLocation NORMAL_TURTLE_MODEL = new ModelResourceLocation(ComputerCraftAPI.MOD_ID, "turtle_normal", "inventory");
-    private static final ModelResourceLocation ADVANCED_TURTLE_MODEL = new ModelResourceLocation(ComputerCraftAPI.MOD_ID, "turtle_advanced", "inventory");
     private static final ResourceLocation COLOUR_TURTLE_MODEL = new ResourceLocation(ComputerCraftAPI.MOD_ID, "block/turtle_colour");
     private static final ResourceLocation ELF_OVERLAY_MODEL = new ResourceLocation(ComputerCraftAPI.MOD_ID, "block/turtle_elf_overlay");
 
@@ -42,13 +38,6 @@ public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBloc
         font = context.getFont();
     }
 
-    public static ResourceLocation getTurtleModel(ComputerFamily family, boolean coloured) {
-        return switch (family) {
-            default -> coloured ? COLOUR_TURTLE_MODEL : NORMAL_TURTLE_MODEL;
-            case ADVANCED -> coloured ? COLOUR_TURTLE_MODEL : ADVANCED_TURTLE_MODEL;
-        };
-    }
-
     public static @Nullable ResourceLocation getTurtleOverlayModel(@Nullable ResourceLocation overlay, boolean christmas) {
         if (overlay != null) return overlay;
         if (christmas) return ELF_OVERLAY_MODEL;
@@ -78,7 +67,6 @@ public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBloc
             var matrix = transform.last().pose();
             var opacity = (int) (mc.options.getBackgroundOpacity(0.25f) * 255) << 24;
             var width = -font.width(label) / 2.0f;
-            // TODO: Check this looks okay
             font.drawInBatch(label, width, (float) 0, 0x20ffffff, false, matrix, buffers, Font.DisplayMode.SEE_THROUGH, opacity, lightmapCoord);
             font.drawInBatch(label, width, (float) 0, 0xffffffff, false, matrix, buffers, Font.DisplayMode.NORMAL, 0, lightmapCoord);
 
@@ -96,10 +84,18 @@ public class TurtleBlockEntityRenderer implements BlockEntityRenderer<TurtleBloc
 
         // Render the turtle
         var colour = turtle.getColour();
-        var family = turtle.getFamily();
         var overlay = turtle.getOverlay();
 
-        renderModel(transform, buffers, lightmapCoord, overlayLight, getTurtleModel(family, colour != -1), colour == -1 ? null : new int[]{ colour });
+        if (colour == -1) {
+            // Render the turtle using its item model.
+            var modelManager = Minecraft.getInstance().getItemRenderer().getItemModelShaper();
+            var model = modelManager.getItemModel(turtle.getBlockState().getBlock().asItem());
+            if (model == null) model = modelManager.getModelManager().getMissingModel();
+            renderModel(transform, buffers, lightmapCoord, overlayLight, model, null);
+        } else {
+            // Otherwise render it using the colour item.
+            renderModel(transform, buffers, lightmapCoord, overlayLight, COLOUR_TURTLE_MODEL, new int[]{ colour });
+        }
 
         // Render the overlay
         var overlayModel = getTurtleOverlayModel(overlay, Holiday.getCurrent() == Holiday.CHRISTMAS);
diff --git a/projects/common/src/main/java/dan200/computercraft/data/RecipeProvider.java b/projects/common/src/main/java/dan200/computercraft/data/RecipeProvider.java
index 719f9a08b..23b91d6ef 100644
--- a/projects/common/src/main/java/dan200/computercraft/data/RecipeProvider.java
+++ b/projects/common/src/main/java/dan200/computercraft/data/RecipeProvider.java
@@ -13,7 +13,6 @@ import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.core.util.Colour;
 import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.common.IColouredItem;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.platform.PlatformHelper;
 import dan200.computercraft.shared.platform.RecipeIngredients;
 import dan200.computercraft.shared.platform.RegistryWrappers;
@@ -38,7 +37,6 @@ import net.minecraft.world.level.ItemLike;
 import net.minecraft.world.level.block.Blocks;
 
 import java.util.List;
-import java.util.Locale;
 import java.util.UUID;
 import java.util.function.Consumer;
 
@@ -106,14 +104,13 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
     private void turtleUpgrades(Consumer<FinishedRecipe> add) {
         for (var turtleItem : turtleItems()) {
             var base = turtleItem.create(-1, null, -1, null, null, 0, null);
-
-            var nameId = turtleItem.getFamily().name().toLowerCase(Locale.ROOT);
+            var name = RegistryWrappers.ITEMS.getKey(turtleItem);
 
             for (var upgrade : turtleUpgrades.getGeneratedUpgrades()) {
                 var result = turtleItem.create(-1, null, -1, null, UpgradeData.ofDefault(upgrade), -1, null);
                 ShapedRecipeBuilder
                     .shaped(RecipeCategory.REDSTONE, result.getItem())
-                    .group(String.format("%s:turtle_%s", ComputerCraftAPI.MOD_ID, nameId))
+                    .group(name.toString())
                     .pattern("#T")
                     .define('T', base.getItem())
                     .define('#', upgrade.getCraftingItem().getItem())
@@ -121,9 +118,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
                         inventoryChange(base.getItem(), upgrade.getCraftingItem().getItem()))
                     .save(
                         RecipeWrapper.wrap(ModRegistry.RecipeSerializers.IMPOSTOR_SHAPED.get(), add).withResultTag(result.getTag()),
-                        new ResourceLocation(ComputerCraftAPI.MOD_ID, String.format("turtle_%s/%s/%s",
-                            nameId, upgrade.getUpgradeID().getNamespace(), upgrade.getUpgradeID().getPath()
-                        ))
+                        name.withSuffix(String.format("/%s/%s", upgrade.getUpgradeID().getNamespace(), upgrade.getUpgradeID().getPath()))
                     );
             }
         }
@@ -141,15 +136,13 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
     private void pocketUpgrades(Consumer<FinishedRecipe> add) {
         for (var pocket : pocketComputerItems()) {
             var base = pocket.create(-1, null, -1, null);
-            if (base.isEmpty()) continue;
-
-            var nameId = pocket.getFamily().name().toLowerCase(Locale.ROOT);
+            var name = RegistryWrappers.ITEMS.getKey(pocket).withPath(x -> x.replace("pocket_computer_", "pocket_"));
 
             for (var upgrade : pocketUpgrades.getGeneratedUpgrades()) {
                 var result = pocket.create(-1, null, -1, UpgradeData.ofDefault(upgrade));
                 ShapedRecipeBuilder
                     .shaped(RecipeCategory.REDSTONE, result.getItem())
-                    .group(String.format("%s:pocket_%s", ComputerCraftAPI.MOD_ID, nameId))
+                    .group(name.toString())
                     .pattern("#")
                     .pattern("P")
                     .define('P', base.getItem())
@@ -158,9 +151,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
                         inventoryChange(base.getItem(), upgrade.getCraftingItem().getItem()))
                     .save(
                         RecipeWrapper.wrap(ModRegistry.RecipeSerializers.IMPOSTOR_SHAPED.get(), add).withResultTag(result.getTag()),
-                        new ResourceLocation(ComputerCraftAPI.MOD_ID, String.format("pocket_%s/%s/%s",
-                            nameId, upgrade.getUpgradeID().getNamespace(), upgrade.getUpgradeID().getPath()
-                        ))
+                        name.withSuffix(String.format("/%s/%s", upgrade.getUpgradeID().getNamespace(), upgrade.getUpgradeID().getPath()))
                     );
             }
         }
@@ -190,12 +181,10 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
     private void turtleOverlay(Consumer<FinishedRecipe> add, String overlay, Consumer<ShapelessRecipeBuilder> build) {
         for (var turtleItem : turtleItems()) {
             var base = turtleItem.create(-1, null, -1, null, null, 0, null);
-
-            var nameId = turtleItem.getFamily().name().toLowerCase(Locale.ROOT);
-            var group = "%s:turtle_%s_overlay".formatted(ComputerCraftAPI.MOD_ID, nameId);
+            var name = RegistryWrappers.ITEMS.getKey(turtleItem);
 
             var builder = ShapelessRecipeBuilder.shapeless(RecipeCategory.REDSTONE, base.getItem())
-                .group(group)
+                .group(name.withSuffix("_overlay").toString())
                 .unlockedBy("has_turtle", inventoryChange(base.getItem()));
             build.accept(builder);
             builder
@@ -204,7 +193,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
                     RecipeWrapper
                         .wrap(ModRegistry.RecipeSerializers.TURTLE_OVERLAY.get(), add)
                         .withExtraData(x -> x.addProperty("overlay", new ResourceLocation(ComputerCraftAPI.MOD_ID, "block/" + overlay).toString())),
-                    new ResourceLocation(ComputerCraftAPI.MOD_ID, "turtle_%s_overlays/%s".formatted(nameId, overlay))
+                    name.withSuffix("_overlays/" + overlay)
                 );
         }
     }
@@ -253,7 +242,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .define('C', ModRegistry.Items.COMPUTER_NORMAL.get())
             .unlockedBy("has_components", inventoryChange(itemPredicate(ModRegistry.Items.COMPUTER_NORMAL.get()), itemPredicate(ingredients.goldIngot())))
             .save(
-                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get(), add).withExtraData(family(ComputerFamily.ADVANCED)),
+                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get(), add),
                 new ResourceLocation(ComputerCraftAPI.MOD_ID, "computer_advanced_upgrade")
             );
 
@@ -277,7 +266,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .define('C', ModRegistry.Items.COMPUTER_NORMAL.get())
             .define('I', ingredients.woodenChest())
             .unlockedBy("has_computer", inventoryChange(ModRegistry.Items.COMPUTER_NORMAL.get()))
-            .save(RecipeWrapper.wrap(ModRegistry.RecipeSerializers.TURTLE.get(), add).withExtraData(family(ComputerFamily.NORMAL)));
+            .save(RecipeWrapper.wrap(ModRegistry.RecipeSerializers.TURTLE.get(), add));
 
         ShapedRecipeBuilder
             .shaped(RecipeCategory.REDSTONE, ModRegistry.Blocks.TURTLE_ADVANCED.get())
@@ -288,7 +277,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .define('C', ModRegistry.Items.COMPUTER_ADVANCED.get())
             .define('I', ingredients.woodenChest())
             .unlockedBy("has_computer", inventoryChange(ModRegistry.Items.COMPUTER_NORMAL.get()))
-            .save(RecipeWrapper.wrap(ModRegistry.RecipeSerializers.TURTLE.get(), add).withExtraData(family(ComputerFamily.ADVANCED)));
+            .save(RecipeWrapper.wrap(ModRegistry.RecipeSerializers.TURTLE.get(), add));
 
         ShapedRecipeBuilder
             .shaped(RecipeCategory.REDSTONE, ModRegistry.Blocks.TURTLE_ADVANCED.get())
@@ -300,7 +289,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .define('B', ingredients.goldBlock())
             .unlockedBy("has_components", inventoryChange(itemPredicate(ModRegistry.Items.TURTLE_NORMAL.get()), itemPredicate(ingredients.goldIngot())))
             .save(
-                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get(), add).withExtraData(family(ComputerFamily.ADVANCED)),
+                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get(), add),
                 new ResourceLocation(ComputerCraftAPI.MOD_ID, "turtle_advanced_upgrade")
             );
 
@@ -367,7 +356,7 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
             .define('C', ModRegistry.Items.POCKET_COMPUTER_NORMAL.get())
             .unlockedBy("has_components", inventoryChange(itemPredicate(ModRegistry.Items.POCKET_COMPUTER_NORMAL.get()), itemPredicate(ingredients.goldIngot())))
             .save(
-                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get(), add).withExtraData(family(ComputerFamily.ADVANCED)),
+                RecipeWrapper.wrap(ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get(), add),
                 new ResourceLocation(ComputerCraftAPI.MOD_ID, "pocket_computer_advanced_upgrade")
             );
 
@@ -519,10 +508,6 @@ class RecipeProvider extends net.minecraft.data.recipes.RecipeProvider {
         return tag;
     }
 
-    private static Consumer<JsonObject> family(ComputerFamily family) {
-        return json -> json.addProperty("family", family.getSerializedName());
-    }
-
     private static void addSpecial(Consumer<FinishedRecipe> add, SimpleCraftingRecipeSerializer<?> special) {
         SpecialRecipeBuilder.special(special).save(add, RegistryWrappers.RECIPE_SERIALIZERS.getKey(special).toString());
     }
diff --git a/projects/common/src/main/java/dan200/computercraft/data/TagProvider.java b/projects/common/src/main/java/dan200/computercraft/data/TagProvider.java
index 798e605d7..9b207e09d 100644
--- a/projects/common/src/main/java/dan200/computercraft/data/TagProvider.java
+++ b/projects/common/src/main/java/dan200/computercraft/data/TagProvider.java
@@ -79,6 +79,8 @@ class TagProvider {
             ModRegistry.Blocks.WIRED_MODEM_FULL.get(),
             ModRegistry.Blocks.CABLE.get()
         );
+
+        tags.tag(BlockTags.WITHER_IMMUNE).add(ModRegistry.Blocks.COMPUTER_COMMAND.get());
     }
 
     public static void itemTags(ItemTagConsumer tags) {
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/ModRegistry.java b/projects/common/src/main/java/dan200/computercraft/shared/ModRegistry.java
index 1af983037..fab124915 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/ModRegistry.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/ModRegistry.java
@@ -34,6 +34,7 @@ import dan200.computercraft.shared.computer.inventory.ViewComputerMenu;
 import dan200.computercraft.shared.computer.items.CommandComputerItem;
 import dan200.computercraft.shared.computer.items.ComputerItem;
 import dan200.computercraft.shared.computer.recipe.ComputerUpgradeRecipe;
+import dan200.computercraft.shared.config.Config;
 import dan200.computercraft.shared.data.BlockNamedEntityLootCondition;
 import dan200.computercraft.shared.data.ConstantLootConditionSerializer;
 import dan200.computercraft.shared.data.HasComputerIdLootCondition;
@@ -139,19 +140,17 @@ public final class ModRegistry {
         }
 
         public static final RegistryEntry<ComputerBlock<ComputerBlockEntity>> COMPUTER_NORMAL = REGISTRY.register("computer_normal",
-            () -> new ComputerBlock<>(computerProperties().mapColor(MapColor.STONE), ComputerFamily.NORMAL, BlockEntities.COMPUTER_NORMAL));
+            () -> new ComputerBlock<>(computerProperties().mapColor(MapColor.STONE), BlockEntities.COMPUTER_NORMAL));
         public static final RegistryEntry<ComputerBlock<ComputerBlockEntity>> COMPUTER_ADVANCED = REGISTRY.register("computer_advanced",
-            () -> new ComputerBlock<>(computerProperties().mapColor(MapColor.GOLD), ComputerFamily.ADVANCED, BlockEntities.COMPUTER_ADVANCED));
+            () -> new ComputerBlock<>(computerProperties().mapColor(MapColor.GOLD), BlockEntities.COMPUTER_ADVANCED));
 
-        public static final RegistryEntry<ComputerBlock<CommandComputerBlockEntity>> COMPUTER_COMMAND = REGISTRY.register("computer_command", () -> new CommandComputerBlock<>(
-            computerProperties().strength(-1, 6000000.0F),
-            ComputerFamily.COMMAND, BlockEntities.COMPUTER_COMMAND
-        ));
+        public static final RegistryEntry<ComputerBlock<CommandComputerBlockEntity>> COMPUTER_COMMAND = REGISTRY.register("computer_command",
+            () -> new CommandComputerBlock<>(computerProperties().strength(-1, 6000000.0F), BlockEntities.COMPUTER_COMMAND));
 
         public static final RegistryEntry<TurtleBlock> TURTLE_NORMAL = REGISTRY.register("turtle_normal",
-            () -> new TurtleBlock(turtleProperties().mapColor(MapColor.STONE), ComputerFamily.NORMAL, BlockEntities.TURTLE_NORMAL));
+            () -> new TurtleBlock(turtleProperties().mapColor(MapColor.STONE), BlockEntities.TURTLE_NORMAL));
         public static final RegistryEntry<TurtleBlock> TURTLE_ADVANCED = REGISTRY.register("turtle_advanced",
-            () -> new TurtleBlock(turtleProperties().mapColor(MapColor.GOLD), ComputerFamily.ADVANCED, BlockEntities.TURTLE_ADVANCED));
+            () -> new TurtleBlock(turtleProperties().mapColor(MapColor.GOLD).explosionResistance(TurtleBlock.IMMUNE_EXPLOSION_RESISTANCE), BlockEntities.TURTLE_ADVANCED));
 
         public static final RegistryEntry<SpeakerBlock> SPEAKER = REGISTRY.register("speaker", () -> new SpeakerBlock(properties().mapColor(MapColor.STONE)));
         public static final RegistryEntry<DiskDriveBlock> DISK_DRIVE = REGISTRY.register("disk_drive", () -> new DiskDriveBlock(properties().mapColor(MapColor.STONE)));
@@ -192,9 +191,9 @@ public final class ModRegistry {
             ofBlock(Blocks.COMPUTER_COMMAND, (p, s) -> new CommandComputerBlockEntity(BlockEntities.COMPUTER_COMMAND.get(), p, s));
 
         public static final RegistryEntry<BlockEntityType<TurtleBlockEntity>> TURTLE_NORMAL =
-            ofBlock(Blocks.TURTLE_NORMAL, (p, s) -> new TurtleBlockEntity(BlockEntities.TURTLE_NORMAL.get(), p, s, ComputerFamily.NORMAL));
+            ofBlock(Blocks.TURTLE_NORMAL, (p, s) -> new TurtleBlockEntity(BlockEntities.TURTLE_NORMAL.get(), p, s, () -> Config.turtleFuelLimit, ComputerFamily.NORMAL));
         public static final RegistryEntry<BlockEntityType<TurtleBlockEntity>> TURTLE_ADVANCED =
-            ofBlock(Blocks.TURTLE_ADVANCED, (p, s) -> new TurtleBlockEntity(BlockEntities.TURTLE_ADVANCED.get(), p, s, ComputerFamily.ADVANCED));
+            ofBlock(Blocks.TURTLE_ADVANCED, (p, s) -> new TurtleBlockEntity(BlockEntities.TURTLE_ADVANCED.get(), p, s, () -> Config.advancedTurtleFuelLimit, ComputerFamily.ADVANCED));
 
         public static final RegistryEntry<BlockEntityType<SpeakerBlockEntity>> SPEAKER =
             ofBlock(Blocks.SPEAKER, (p, s) -> new SpeakerBlockEntity(BlockEntities.SPEAKER.get(), p, s));
@@ -311,7 +310,10 @@ public final class ModRegistry {
             () -> new MenuType<>(PrinterMenu::new, FeatureFlags.VANILLA_SET));
 
         public static final RegistryEntry<MenuType<HeldItemMenu>> PRINTOUT = REGISTRY.register("printout",
-            () -> ContainerData.toType(HeldItemContainerData::new, HeldItemMenu::createPrintout));
+            () -> ContainerData.toType(
+                HeldItemContainerData::new,
+                (id, inventory, data) -> new HeldItemMenu(Menus.PRINTOUT.get(), id, inventory.player, data.getHand())
+            ));
 
         public static final RegistryEntry<MenuType<ViewComputerMenu>> VIEW_COMPUTER = REGISTRY.register("view_computer",
             () -> ContainerData.toType(ComputerContainerData::new, ViewComputerMenu::new));
@@ -371,11 +373,11 @@ public final class ModRegistry {
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<ClearColourRecipe>> DYEABLE_ITEM_CLEAR = simple("clear_colour", ClearColourRecipe::new);
         public static final RegistryEntry<RecipeSerializer<TurtleRecipe>> TURTLE = REGISTRY.register("turtle", () -> TurtleRecipe.validatingSerialiser(TurtleRecipe::of));
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<TurtleUpgradeRecipe>> TURTLE_UPGRADE = simple("turtle_upgrade", TurtleUpgradeRecipe::new);
-        public static final RegistryEntry<RecipeSerializer<TurtleOverlayRecipe>> TURTLE_OVERLAY = REGISTRY.register("turtle_overlay", TurtleOverlayRecipe.Serializer::new);
+        public static final RegistryEntry<RecipeSerializer<TurtleOverlayRecipe>> TURTLE_OVERLAY = REGISTRY.register("turtle_overlay", TurtleOverlayRecipe.Serialiser::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<PocketComputerUpgradeRecipe>> POCKET_COMPUTER_UPGRADE = simple("pocket_computer_upgrade", PocketComputerUpgradeRecipe::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<PrintoutRecipe>> PRINTOUT = simple("printout", PrintoutRecipe::new);
         public static final RegistryEntry<SimpleCraftingRecipeSerializer<DiskRecipe>> DISK = simple("disk", DiskRecipe::new);
-        public static final RegistryEntry<RecipeSerializer<ComputerUpgradeRecipe>> COMPUTER_UPGRADE = REGISTRY.register("computer_upgrade", ComputerUpgradeRecipe.Serializer::new);
+        public static final RegistryEntry<RecipeSerializer<ComputerUpgradeRecipe>> COMPUTER_UPGRADE = REGISTRY.register("computer_upgrade", () -> CustomShapedRecipe.validatingSerialiser(ComputerUpgradeRecipe::of));
     }
 
     public static class Permissions {
@@ -464,8 +466,8 @@ public final class ModRegistry {
      * Register any objects which must be done on the main thread.
      */
     public static void registerMainThread() {
-        CauldronInteraction.WATER.put(ModRegistry.Items.TURTLE_NORMAL.get(), TurtleItem.CAULDRON_INTERACTION);
-        CauldronInteraction.WATER.put(ModRegistry.Items.TURTLE_ADVANCED.get(), TurtleItem.CAULDRON_INTERACTION);
+        CauldronInteraction.WATER.put(Items.TURTLE_NORMAL.get(), TurtleItem.CAULDRON_INTERACTION);
+        CauldronInteraction.WATER.put(Items.TURTLE_ADVANCED.get(), TurtleItem.CAULDRON_INTERACTION);
     }
 
     private static void addTurtle(CreativeModeTab.Output out, TurtleItem turtle) {
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/common/HeldItemMenu.java b/projects/common/src/main/java/dan200/computercraft/shared/common/HeldItemMenu.java
index bd256a8d4..7a4c5895d 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/common/HeldItemMenu.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/common/HeldItemMenu.java
@@ -4,8 +4,6 @@
 
 package dan200.computercraft.shared.common;
 
-import dan200.computercraft.shared.ModRegistry;
-import dan200.computercraft.shared.network.container.HeldItemContainerData;
 import net.minecraft.network.chat.Component;
 import net.minecraft.world.InteractionHand;
 import net.minecraft.world.MenuProvider;
@@ -28,10 +26,6 @@ public class HeldItemMenu extends AbstractContainerMenu {
         stack = player.getItemInHand(hand).copy();
     }
 
-    public static HeldItemMenu createPrintout(int id, Inventory inventory, HeldItemContainerData data) {
-        return new HeldItemMenu(ModRegistry.Menus.PRINTOUT.get(), id, inventory.player, data.getHand());
-    }
-
     public ItemStack getStack() {
         return stack;
     }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java
index 9438da0e0..2bd6f00f4 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/AbstractComputerBlock.java
@@ -7,7 +7,6 @@ package dan200.computercraft.shared.computer.blocks;
 import dan200.computercraft.annotations.ForgeOverride;
 import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.shared.common.IBundledRedstoneBlock;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.items.IComputerItem;
 import dan200.computercraft.shared.platform.RegistryEntry;
 import dan200.computercraft.shared.util.BlockEntityHelpers;
@@ -42,13 +41,11 @@ import javax.annotation.Nullable;
 public abstract class AbstractComputerBlock<T extends AbstractComputerBlockEntity> extends HorizontalDirectionalBlock implements IBundledRedstoneBlock, EntityBlock {
     private static final ResourceLocation DROP = new ResourceLocation(ComputerCraftAPI.MOD_ID, "computer");
 
-    private final ComputerFamily family;
     protected final RegistryEntry<BlockEntityType<T>> type;
     private final BlockEntityTicker<T> serverTicker = (level, pos, state, computer) -> computer.serverTick();
 
-    protected AbstractComputerBlock(Properties settings, ComputerFamily family, RegistryEntry<BlockEntityType<T>> type) {
+    protected AbstractComputerBlock(Properties settings, RegistryEntry<BlockEntityType<T>> type) {
         super(settings);
-        this.family = family;
         this.type = type;
     }
 
@@ -82,10 +79,6 @@ public abstract class AbstractComputerBlock<T extends AbstractComputerBlockEntit
 
     protected abstract ItemStack getItem(AbstractComputerBlockEntity tile);
 
-    public ComputerFamily getFamily() {
-        return family;
-    }
-
     @Override
     @Deprecated
     public int getSignal(BlockState state, BlockGetter world, BlockPos pos, Direction incomingSide) {
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/CommandComputerBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/CommandComputerBlock.java
index 43606df51..4e8ad3535 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/CommandComputerBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/CommandComputerBlock.java
@@ -4,7 +4,6 @@
 
 package dan200.computercraft.shared.computer.blocks;
 
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.platform.RegistryEntry;
 import net.minecraft.world.level.block.GameMasterBlock;
 import net.minecraft.world.level.block.entity.BlockEntityType;
@@ -17,7 +16,7 @@ import net.minecraft.world.level.block.entity.BlockEntityType;
  * @see dan200.computercraft.shared.computer.items.CommandComputerItem
  */
 public class CommandComputerBlock<T extends CommandComputerBlockEntity> extends ComputerBlock<T> implements GameMasterBlock {
-    public CommandComputerBlock(Properties settings, ComputerFamily family, RegistryEntry<BlockEntityType<T>> type) {
-        super(settings, family, type);
+    public CommandComputerBlock(Properties settings, RegistryEntry<BlockEntityType<T>> type) {
+        super(settings, type);
     }
 }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlock.java
index ba22baf20..44a3e85f4 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlock.java
@@ -4,9 +4,8 @@
 
 package dan200.computercraft.shared.computer.blocks;
 
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ComputerState;
-import dan200.computercraft.shared.computer.items.ComputerItemFactory;
+import dan200.computercraft.shared.computer.items.ComputerItem;
 import dan200.computercraft.shared.platform.RegistryEntry;
 import net.minecraft.core.Direction;
 import net.minecraft.world.item.ItemStack;
@@ -25,8 +24,8 @@ public class ComputerBlock<T extends ComputerBlockEntity> extends AbstractComput
     public static final EnumProperty<ComputerState> STATE = EnumProperty.create("state", ComputerState.class);
     public static final DirectionProperty FACING = BlockStateProperties.HORIZONTAL_FACING;
 
-    public ComputerBlock(Properties settings, ComputerFamily family, RegistryEntry<BlockEntityType<T>> type) {
-        super(settings, family, type);
+    public ComputerBlock(Properties settings, RegistryEntry<BlockEntityType<T>> type) {
+        super(settings, type);
         registerDefaultState(defaultBlockState()
             .setValue(FACING, Direction.NORTH)
             .setValue(STATE, ComputerState.OFF)
@@ -46,6 +45,9 @@ public class ComputerBlock<T extends ComputerBlockEntity> extends AbstractComput
 
     @Override
     protected ItemStack getItem(AbstractComputerBlockEntity tile) {
-        return tile instanceof ComputerBlockEntity ? ComputerItemFactory.create((ComputerBlockEntity) tile) : ItemStack.EMPTY;
+        if (!(tile instanceof ComputerBlockEntity computer)) return ItemStack.EMPTY;
+        if (!(asItem() instanceof ComputerItem item)) return ItemStack.EMPTY;
+
+        return item.create(computer.getComputerID(), computer.getLabel());
     }
 }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlockEntity.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlockEntity.java
index 598841758..6aee79628 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlockEntity.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/blocks/ComputerBlockEntity.java
@@ -32,11 +32,9 @@ public class ComputerBlockEntity extends AbstractComputerBlockEntity {
 
     @Override
     protected ServerComputer createComputer(int id) {
-        var family = getFamily();
         return new ServerComputer(
             (ServerLevel) getLevel(), getBlockPos(), id, label,
-            family, Config.computerTermWidth,
-            Config.computerTermHeight
+            getFamily(), Config.computerTermWidth, Config.computerTermHeight
         );
     }
 
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/core/ComputerFamily.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/core/ComputerFamily.java
index da1b912c2..491fb0a5f 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/core/ComputerFamily.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/core/ComputerFamily.java
@@ -4,33 +4,8 @@
 
 package dan200.computercraft.shared.computer.core;
 
-import com.google.gson.JsonObject;
-import com.google.gson.JsonSyntaxException;
-import net.minecraft.util.GsonHelper;
-import net.minecraft.util.StringRepresentable;
-
-public enum ComputerFamily implements StringRepresentable {
-    NORMAL("normal"),
-    ADVANCED("advanced"),
-    COMMAND("command");
-
-    private final String name;
-
-    ComputerFamily(String name) {
-        this.name = name;
-    }
-
-    public static ComputerFamily getFamily(JsonObject json, String name) {
-        var familyName = GsonHelper.getAsString(json, name);
-        for (var family : values()) {
-            if (family.getSerializedName().equalsIgnoreCase(familyName)) return family;
-        }
-
-        throw new JsonSyntaxException("Unknown computer family '" + familyName + "' for field " + name);
-    }
-
-    @Override
-    public String getSerializedName() {
-        return name;
-    }
+public enum ComputerFamily {
+    NORMAL,
+    ADVANCED,
+    COMMAND,
 }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/AbstractComputerItem.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/AbstractComputerItem.java
index 5c40474de..f9499e7dc 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/AbstractComputerItem.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/AbstractComputerItem.java
@@ -8,7 +8,6 @@ import dan200.computercraft.api.ComputerCraftAPI;
 import dan200.computercraft.api.filesystem.Mount;
 import dan200.computercraft.api.media.IMedia;
 import dan200.computercraft.shared.computer.blocks.AbstractComputerBlock;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.config.Config;
 import net.minecraft.ChatFormatting;
 import net.minecraft.network.chat.Component;
@@ -22,11 +21,8 @@ import javax.annotation.Nullable;
 import java.util.List;
 
 public abstract class AbstractComputerItem extends BlockItem implements IComputerItem, IMedia {
-    private final ComputerFamily family;
-
     public AbstractComputerItem(AbstractComputerBlock<?> block, Properties settings) {
         super(block, settings);
-        family = block.getFamily();
     }
 
     @Override
@@ -45,13 +41,6 @@ public abstract class AbstractComputerItem extends BlockItem implements ICompute
         return IComputerItem.super.getLabel(stack);
     }
 
-    @Override
-    public final ComputerFamily getFamily() {
-        return family;
-    }
-
-    // IMedia implementation
-
     @Override
     public boolean setLabel(ItemStack stack, @Nullable String label) {
         if (label != null) {
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItem.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItem.java
index 350d11c9b..56170e454 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItem.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItem.java
@@ -5,8 +5,8 @@
 package dan200.computercraft.shared.computer.items;
 
 import dan200.computercraft.shared.computer.blocks.ComputerBlock;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import net.minecraft.network.chat.Component;
+import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 
 import javax.annotation.Nullable;
@@ -24,9 +24,9 @@ public class ComputerItem extends AbstractComputerItem {
     }
 
     @Override
-    public ItemStack withFamily(ItemStack stack, ComputerFamily family) {
-        var result = ComputerItemFactory.create(getComputerID(stack), null, family);
-        if (stack.hasCustomHoverName()) result.setHoverName(stack.getHoverName());
-        return result;
+    public ItemStack changeItem(ItemStack stack, Item newItem) {
+        return newItem instanceof ComputerItem computer
+            ? computer.create(getComputerID(stack), getLabel(stack))
+            : ItemStack.EMPTY;
     }
 }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItemFactory.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItemFactory.java
deleted file mode 100644
index 127b47903..000000000
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/ComputerItemFactory.java
+++ /dev/null
@@ -1,29 +0,0 @@
-// Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
-//
-// SPDX-License-Identifier: LicenseRef-CCPL
-
-package dan200.computercraft.shared.computer.items;
-
-import dan200.computercraft.shared.ModRegistry;
-import dan200.computercraft.shared.computer.blocks.ComputerBlockEntity;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
-import net.minecraft.world.item.ItemStack;
-
-import javax.annotation.Nullable;
-
-public final class ComputerItemFactory {
-    private ComputerItemFactory() {
-    }
-
-    public static ItemStack create(ComputerBlockEntity tile) {
-        return create(tile.getComputerID(), tile.getLabel(), tile.getFamily());
-    }
-
-    public static ItemStack create(int id, @Nullable String label, ComputerFamily family) {
-        return switch (family) {
-            case NORMAL -> ModRegistry.Items.COMPUTER_NORMAL.get().create(id, label);
-            case ADVANCED -> ModRegistry.Items.COMPUTER_ADVANCED.get().create(id, label);
-            case COMMAND -> ModRegistry.Items.COMPUTER_COMMAND.get().create(id, label);
-        };
-    }
-}
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/IComputerItem.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/IComputerItem.java
index c88b93916..03bcb762e 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/items/IComputerItem.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/items/IComputerItem.java
@@ -4,7 +4,7 @@
 
 package dan200.computercraft.shared.computer.items;
 
-import dan200.computercraft.shared.computer.core.ComputerFamily;
+import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 
 import javax.annotation.Nullable;
@@ -21,7 +21,15 @@ public interface IComputerItem {
         return stack.hasCustomHoverName() ? stack.getHoverName().getString() : null;
     }
 
-    ComputerFamily getFamily();
-
-    ItemStack withFamily(ItemStack stack, ComputerFamily family);
+    /**
+     * Create a new stack, changing the underlying item.
+     * <p>
+     * This should copy the computer's data to a different item of the same type (for instance, converting a normal
+     * computer to an advanced one).
+     *
+     * @param stack   The current computer stack.
+     * @param newItem The new item.
+     * @return The new stack, possibly {@linkplain ItemStack#EMPTY empty} if {@code newItem} is of the same type.
+     */
+    ItemStack changeItem(ItemStack stack, Item newItem);
 }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerUpgradeRecipe.java b/projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerUpgradeRecipe.java
index 075695752..cec37135e 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerUpgradeRecipe.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/computer/recipe/ComputerUpgradeRecipe.java
@@ -4,57 +4,44 @@
 
 package dan200.computercraft.shared.computer.recipe;
 
-import com.google.gson.JsonObject;
+import com.mojang.serialization.DataResult;
 import dan200.computercraft.shared.ModRegistry;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.items.IComputerItem;
 import dan200.computercraft.shared.recipe.ShapedRecipeSpec;
-import net.minecraft.network.FriendlyByteBuf;
 import net.minecraft.resources.ResourceLocation;
+import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.item.crafting.RecipeSerializer;
 
 /**
- * A recipe which "upgrades" a {@linkplain IComputerItem computer}, converting it from one {@linkplain ComputerFamily
- * family} to another.
+ * A recipe which "upgrades" a {@linkplain IComputerItem computer}, converting to it a new item (for instance a normal
+ * turtle to an advanced one).
+ *
+ * @see IComputerItem#changeItem(ItemStack, Item)
  */
 public final class ComputerUpgradeRecipe extends ComputerConvertRecipe {
-    private final ComputerFamily family;
+    private final Item result;
 
-    private ComputerUpgradeRecipe(ResourceLocation identifier, ShapedRecipeSpec recipe, ComputerFamily family) {
+    private ComputerUpgradeRecipe(ResourceLocation identifier, ShapedRecipeSpec recipe) {
         super(identifier, recipe);
-        this.family = family;
+        this.result = recipe.result().getItem();
+    }
+
+    public static DataResult<ComputerUpgradeRecipe> of(ResourceLocation id, ShapedRecipeSpec recipe) {
+        if (!(recipe.result().getItem() instanceof IComputerItem)) {
+            return DataResult.error(() -> recipe.result().getItem() + " is not a computer item");
+        }
+
+        return DataResult.success(new ComputerUpgradeRecipe(id, recipe));
     }
 
     @Override
     protected ItemStack convert(IComputerItem item, ItemStack stack) {
-        return item.withFamily(stack, family);
+        return item.changeItem(stack, result);
     }
 
     @Override
     public RecipeSerializer<ComputerUpgradeRecipe> getSerializer() {
         return ModRegistry.RecipeSerializers.COMPUTER_UPGRADE.get();
     }
-
-    public static class Serializer implements RecipeSerializer<ComputerUpgradeRecipe> {
-        @Override
-        public ComputerUpgradeRecipe fromJson(ResourceLocation identifier, JsonObject json) {
-            var recipe = ShapedRecipeSpec.fromJson(json);
-            var family = ComputerFamily.getFamily(json, "family");
-            return new ComputerUpgradeRecipe(identifier, recipe, family);
-        }
-
-        @Override
-        public ComputerUpgradeRecipe fromNetwork(ResourceLocation identifier, FriendlyByteBuf buf) {
-            var recipe = ShapedRecipeSpec.fromNetwork(buf);
-            var family = buf.readEnum(ComputerFamily.class);
-            return new ComputerUpgradeRecipe(identifier, recipe, family);
-        }
-
-        @Override
-        public void toNetwork(FriendlyByteBuf buf, ComputerUpgradeRecipe recipe) {
-            recipe.toSpec().toNetwork(buf);
-            buf.writeEnum(recipe.family);
-        }
-    }
 }
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/pocket/items/PocketComputerItem.java b/projects/common/src/main/java/dan200/computercraft/shared/pocket/items/PocketComputerItem.java
index c35265e42..c3e731ca3 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/pocket/items/PocketComputerItem.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/pocket/items/PocketComputerItem.java
@@ -12,7 +12,6 @@ import dan200.computercraft.api.pocket.IPocketUpgrade;
 import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.core.computer.ComputerSide;
 import dan200.computercraft.impl.PocketUpgrades;
-import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.common.IColouredItem;
 import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.core.ServerContext;
@@ -60,14 +59,6 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
         this.family = family;
     }
 
-    public static ItemStack create(int id, @Nullable String label, int colour, ComputerFamily family, @Nullable UpgradeData<IPocketUpgrade> upgrade) {
-        return switch (family) {
-            case NORMAL -> ModRegistry.Items.POCKET_COMPUTER_NORMAL.get().create(id, label, colour, upgrade);
-            case ADVANCED -> ModRegistry.Items.POCKET_COMPUTER_ADVANCED.get().create(id, label, colour, upgrade);
-            default -> ItemStack.EMPTY;
-        };
-    }
-
     public ItemStack create(int id, @Nullable String label, int colour, @Nullable UpgradeData<IPocketUpgrade> upgrade) {
         var result = new ItemStack(this);
         if (id >= 0) result.getOrCreateTag().putInt(NBT_ID, id);
@@ -243,17 +234,16 @@ public class PocketComputerItem extends Item implements IComputerItem, IMedia, I
         return IComputerItem.super.getLabel(stack);
     }
 
-    @Override
     public ComputerFamily getFamily() {
         return family;
     }
 
     @Override
-    public ItemStack withFamily(ItemStack stack, ComputerFamily family) {
-        return create(
+    public ItemStack changeItem(ItemStack stack, Item newItem) {
+        return newItem instanceof PocketComputerItem pocket ? pocket.create(
             getComputerID(stack), getLabel(stack), getColour(stack),
-            family, getUpgradeWithData(stack)
-        );
+            getUpgradeWithData(stack)
+        ) : ItemStack.EMPTY;
     }
 
     // IMedia
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/pocket/recipes/PocketComputerUpgradeRecipe.java b/projects/common/src/main/java/dan200/computercraft/shared/pocket/recipes/PocketComputerUpgradeRecipe.java
index b0b25bd87..bf55800a2 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/pocket/recipes/PocketComputerUpgradeRecipe.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/pocket/recipes/PocketComputerUpgradeRecipe.java
@@ -81,7 +81,6 @@ public final class PocketComputerUpgradeRecipe extends CustomRecipe {
         if (upgrade == null) return ItemStack.EMPTY;
 
         // Construct the new stack
-        var family = itemComputer.getFamily();
         var computerID = itemComputer.getComputerID(computer);
         var label = itemComputer.getLabel(computer);
         var colour = itemComputer.getColour(computer);
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlock.java b/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlock.java
index 157bb876b..e2b01fa73 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlock.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlock.java
@@ -10,7 +10,6 @@ import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.shared.computer.blocks.AbstractComputerBlock;
 import dan200.computercraft.shared.computer.blocks.AbstractComputerBlockEntity;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.platform.RegistryEntry;
 import dan200.computercraft.shared.turtle.core.TurtleBrain;
 import dan200.computercraft.shared.turtle.items.TurtleItem;
@@ -52,6 +51,16 @@ import static dan200.computercraft.shared.util.WaterloggableHelpers.getFluidStat
 public class TurtleBlock extends AbstractComputerBlock<TurtleBlockEntity> implements SimpleWaterloggedBlock {
     public static final DirectionProperty FACING = BlockStateProperties.HORIZONTAL_FACING;
 
+    /**
+     * The explosion resistance to use when a turtle is "immune" to explosions.
+     * <p>
+     * This is used as the default explosion resistance for advanced turtles, and the resistance for entity-based
+     * explosions (e.g. creepers).
+     *
+     * @see #getExplosionResistance(BlockState, BlockGetter, BlockPos, Explosion)
+     */
+    public static final float IMMUNE_EXPLOSION_RESISTANCE = 2000f;
+
     private static final VoxelShape DEFAULT_SHAPE = Shapes.box(
         0.125, 0.125, 0.125,
         0.875, 0.875, 0.875
@@ -59,8 +68,8 @@ public class TurtleBlock extends AbstractComputerBlock<TurtleBlockEntity> implem
 
     private final BlockEntityTicker<TurtleBlockEntity> clientTicker = (level, pos, state, computer) -> computer.clientTick();
 
-    public TurtleBlock(Properties settings, ComputerFamily family, RegistryEntry<BlockEntityType<TurtleBlockEntity>> type) {
-        super(settings, family, type);
+    public TurtleBlock(Properties settings, RegistryEntry<BlockEntityType<TurtleBlockEntity>> type) {
+        super(settings, type);
         registerDefaultState(getStateDefinition().any()
             .setValue(FACING, Direction.NORTH)
             .setValue(WATERLOGGED, false)
@@ -149,20 +158,21 @@ public class TurtleBlock extends AbstractComputerBlock<TurtleBlockEntity> implem
     @ForgeOverride
     public float getExplosionResistance(BlockState state, BlockGetter world, BlockPos pos, Explosion explosion) {
         var exploder = explosion.getDirectSourceEntity();
-        if (getFamily() == ComputerFamily.ADVANCED || exploder instanceof LivingEntity || exploder instanceof AbstractHurtingProjectile) {
-            return 2000;
+        if (exploder instanceof LivingEntity || exploder instanceof AbstractHurtingProjectile) {
+            return IMMUNE_EXPLOSION_RESISTANCE;
         }
 
-        return explosionResistance;
+        return getExplosionResistance();
     }
 
     @Override
     protected ItemStack getItem(AbstractComputerBlockEntity tile) {
         if (!(tile instanceof TurtleBlockEntity turtle)) return ItemStack.EMPTY;
+        if (!(asItem() instanceof TurtleItem item)) return ItemStack.EMPTY;
 
         var access = turtle.getAccess();
-        return TurtleItem.create(
-            turtle.getComputerID(), turtle.getLabel(), access.getColour(), turtle.getFamily(),
+        return item.create(
+            turtle.getComputerID(), turtle.getLabel(), access.getColour(),
             withPersistedData(access.getUpgradeWithData(TurtleSide.LEFT)),
             withPersistedData(access.getUpgradeWithData(TurtleSide.RIGHT)),
             access.getFuelLevel(), turtle.getOverlay()
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlockEntity.java b/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlockEntity.java
index e5c9e2f00..87595824b 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlockEntity.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/turtle/blocks/TurtleBlockEntity.java
@@ -38,6 +38,7 @@ import net.minecraft.world.phys.Vec3;
 
 import javax.annotation.Nullable;
 import java.util.Collections;
+import java.util.function.IntSupplier;
 
 public class TurtleBlockEntity extends AbstractComputerBlockEntity implements BasicContainer {
     public static final int INVENTORY_SIZE = 16;
@@ -53,13 +54,17 @@ public class TurtleBlockEntity extends AbstractComputerBlockEntity implements Ba
     private final NonNullList<ItemStack> inventory = NonNullList.withSize(INVENTORY_SIZE, ItemStack.EMPTY);
     private final NonNullList<ItemStack> inventorySnapshot = NonNullList.withSize(INVENTORY_SIZE, ItemStack.EMPTY);
     private boolean inventoryChanged = false;
+
+    private final IntSupplier fuelLimit;
+
     private TurtleBrain brain = new TurtleBrain(this);
     private MoveState moveState = MoveState.NOT_MOVED;
     private @Nullable IPeripheral peripheral;
     private @Nullable Runnable onMoved;
 
-    public TurtleBlockEntity(BlockEntityType<? extends TurtleBlockEntity> type, BlockPos pos, BlockState state, ComputerFamily family) {
+    public TurtleBlockEntity(BlockEntityType<? extends TurtleBlockEntity> type, BlockPos pos, BlockState state, IntSupplier fuelLimit, ComputerFamily family) {
         super(type, pos, state, family);
+        this.fuelLimit = fuelLimit;
     }
 
     boolean hasMoved() {
@@ -172,8 +177,6 @@ public class TurtleBlockEntity extends AbstractComputerBlockEntity implements Ba
         return hasPeripheralUpgradeOnSide(localSide);
     }
 
-    // IDirectionalTile
-
     @Override
     public Direction getDirection() {
         return getBlockState().getValue(TurtleBlock.FACING);
@@ -272,6 +275,10 @@ public class TurtleBlockEntity extends AbstractComputerBlockEntity implements Ba
 
     // Privates
 
+    public int getFuelLimit() {
+        return fuelLimit.getAsInt();
+    }
+
     private boolean hasPeripheralUpgradeOnSide(ComputerSide side) {
         ITurtleUpgrade upgrade;
         switch (side) {
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleBrain.java b/projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleBrain.java
index 1b5728ed2..e399096bf 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleBrain.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/turtle/core/TurtleBrain.java
@@ -395,11 +395,7 @@ public class TurtleBrain implements TurtleAccessInternal {
 
     @Override
     public int getFuelLimit() {
-        if (owner.getFamily() == ComputerFamily.ADVANCED) {
-            return Config.advancedTurtleFuelLimit;
-        } else {
-            return Config.turtleFuelLimit;
-        }
+        return owner.getFuelLimit();
     }
 
     @Override
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/turtle/items/TurtleItem.java b/projects/common/src/main/java/dan200/computercraft/shared/turtle/items/TurtleItem.java
index 640872b23..4b5994900 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/turtle/items/TurtleItem.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/turtle/items/TurtleItem.java
@@ -10,9 +10,7 @@ import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
 import dan200.computercraft.api.upgrades.UpgradeData;
 import dan200.computercraft.impl.TurtleUpgrades;
-import dan200.computercraft.shared.ModRegistry;
 import dan200.computercraft.shared.common.IColouredItem;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
 import dan200.computercraft.shared.computer.items.AbstractComputerItem;
 import dan200.computercraft.shared.turtle.blocks.TurtleBlock;
 import dan200.computercraft.shared.util.NBTUtil;
@@ -20,6 +18,7 @@ import net.minecraft.core.cauldron.CauldronInteraction;
 import net.minecraft.network.chat.Component;
 import net.minecraft.resources.ResourceLocation;
 import net.minecraft.world.InteractionResult;
+import net.minecraft.world.item.Item;
 import net.minecraft.world.item.ItemStack;
 import net.minecraft.world.level.block.LayeredCauldronBlock;
 
@@ -32,20 +31,6 @@ public class TurtleItem extends AbstractComputerItem implements IColouredItem {
         super(block, settings);
     }
 
-    public static ItemStack create(
-        int id, @Nullable String label, int colour, ComputerFamily family,
-        @Nullable UpgradeData<ITurtleUpgrade> leftUpgrade, @Nullable UpgradeData<ITurtleUpgrade> rightUpgrade,
-        int fuelLevel, @Nullable ResourceLocation overlay
-    ) {
-        return switch (family) {
-            case NORMAL ->
-                ModRegistry.Items.TURTLE_NORMAL.get().create(id, label, colour, leftUpgrade, rightUpgrade, fuelLevel, overlay);
-            case ADVANCED ->
-                ModRegistry.Items.TURTLE_ADVANCED.get().create(id, label, colour, leftUpgrade, rightUpgrade, fuelLevel, overlay);
-            default -> ItemStack.EMPTY;
-        };
-    }
-
     public ItemStack create(
         int id, @Nullable String label, int colour,
         @Nullable UpgradeData<ITurtleUpgrade> leftUpgrade, @Nullable UpgradeData<ITurtleUpgrade> rightUpgrade,
@@ -119,13 +104,13 @@ public class TurtleItem extends AbstractComputerItem implements IColouredItem {
     }
 
     @Override
-    public ItemStack withFamily(ItemStack stack, ComputerFamily family) {
-        return create(
+    public ItemStack changeItem(ItemStack stack, Item newItem) {
+        return newItem instanceof TurtleItem turtle ? turtle.create(
             getComputerID(stack), getLabel(stack),
-            getColour(stack), family,
+            getColour(stack),
             getUpgradeWithData(stack, TurtleSide.LEFT), getUpgradeWithData(stack, TurtleSide.RIGHT),
             getFuelLevel(stack), getOverlay(stack)
-        );
+        ) : ItemStack.EMPTY;
     }
 
     public @Nullable ITurtleUpgrade getUpgrade(ItemStack stack, TurtleSide side) {
diff --git a/projects/common/src/main/java/dan200/computercraft/shared/turtle/recipes/TurtleOverlayRecipe.java b/projects/common/src/main/java/dan200/computercraft/shared/turtle/recipes/TurtleOverlayRecipe.java
index 57609c1ce..65d6ee1b2 100644
--- a/projects/common/src/main/java/dan200/computercraft/shared/turtle/recipes/TurtleOverlayRecipe.java
+++ b/projects/common/src/main/java/dan200/computercraft/shared/turtle/recipes/TurtleOverlayRecipe.java
@@ -58,7 +58,7 @@ public class TurtleOverlayRecipe extends CustomShapelessRecipe {
         return ModRegistry.RecipeSerializers.TURTLE_OVERLAY.get();
     }
 
-    public static class Serializer implements RecipeSerializer<TurtleOverlayRecipe> {
+    public static class Serialiser implements RecipeSerializer<TurtleOverlayRecipe> {
         @Override
         public TurtleOverlayRecipe fromJson(ResourceLocation id, JsonObject json) {
             var recipe = ShapelessRecipeSpec.fromJson(json);
diff --git a/projects/fabric/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json b/projects/fabric/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json
index ccbc87c2c..03289f803 100644
--- a/projects/fabric/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json
+++ b/projects/fabric/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:computer_upgrade",
   "category": "redstone",
-  "family": "advanced",
   "key": {"#": {"tag": "c:gold_ingots"}, "C": {"item": "computercraft:computer_normal"}},
   "pattern": ["###", "#C#", "# #"],
   "result": {"item": "computercraft:computer_advanced"},
diff --git a/projects/fabric/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json b/projects/fabric/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json
index ac2f5a9b7..765944e32 100644
--- a/projects/fabric/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json
+++ b/projects/fabric/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:computer_upgrade",
   "category": "redstone",
-  "family": "advanced",
   "key": {"#": {"tag": "c:gold_ingots"}, "C": {"item": "computercraft:pocket_computer_normal"}},
   "pattern": ["###", "#C#", "# #"],
   "result": {"item": "computercraft:pocket_computer_advanced"},
diff --git a/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced.json b/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced.json
index 367b93bc2..a720038df 100644
--- a/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced.json
+++ b/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:turtle",
   "category": "redstone",
-  "family": "advanced",
   "key": {
     "#": {"tag": "c:gold_ingots"},
     "C": {"item": "computercraft:computer_advanced"},
diff --git a/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json b/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json
index 155297a1f..6a50ccec9 100644
--- a/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json
+++ b/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:computer_upgrade",
   "category": "redstone",
-  "family": "advanced",
   "key": {
     "#": {"tag": "c:gold_ingots"},
     "B": {"item": "minecraft:gold_block"},
diff --git a/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_normal.json b/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_normal.json
index eb35293ca..09f79a331 100644
--- a/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_normal.json
+++ b/projects/fabric/src/generated/resources/data/computercraft/recipes/turtle_normal.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:turtle",
   "category": "redstone",
-  "family": "normal",
   "key": {
     "#": {"tag": "c:iron_ingots"},
     "C": {"item": "computercraft:computer_normal"},
diff --git a/projects/fabric/src/generated/resources/data/minecraft/tags/blocks/wither_immune.json b/projects/fabric/src/generated/resources/data/minecraft/tags/blocks/wither_immune.json
new file mode 100644
index 000000000..acf2c81ae
--- /dev/null
+++ b/projects/fabric/src/generated/resources/data/minecraft/tags/blocks/wither_immune.json
@@ -0,0 +1 @@
+{"replace": false, "values": ["computercraft:computer_command"]}
diff --git a/projects/forge/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json b/projects/forge/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json
index 05bf8dc26..3a938c9c1 100644
--- a/projects/forge/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json
+++ b/projects/forge/src/generated/resources/data/computercraft/recipes/computer_advanced_upgrade.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:computer_upgrade",
   "category": "redstone",
-  "family": "advanced",
   "key": {"#": {"tag": "forge:ingots/gold"}, "C": {"item": "computercraft:computer_normal"}},
   "pattern": ["###", "#C#", "# #"],
   "result": {"item": "computercraft:computer_advanced"},
diff --git a/projects/forge/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json b/projects/forge/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json
index a139e02dd..2c5ec0cc8 100644
--- a/projects/forge/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json
+++ b/projects/forge/src/generated/resources/data/computercraft/recipes/pocket_computer_advanced_upgrade.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:computer_upgrade",
   "category": "redstone",
-  "family": "advanced",
   "key": {"#": {"tag": "forge:ingots/gold"}, "C": {"item": "computercraft:pocket_computer_normal"}},
   "pattern": ["###", "#C#", "# #"],
   "result": {"item": "computercraft:pocket_computer_advanced"},
diff --git a/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced.json b/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced.json
index c0485e66a..1e55d8f69 100644
--- a/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced.json
+++ b/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:turtle",
   "category": "redstone",
-  "family": "advanced",
   "key": {
     "#": {"tag": "forge:ingots/gold"},
     "C": {"item": "computercraft:computer_advanced"},
diff --git a/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json b/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json
index a1c522fb8..6b1d7cc89 100644
--- a/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json
+++ b/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_advanced_upgrade.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:computer_upgrade",
   "category": "redstone",
-  "family": "advanced",
   "key": {
     "#": {"tag": "forge:ingots/gold"},
     "B": {"tag": "forge:storage_blocks/gold"},
diff --git a/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_normal.json b/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_normal.json
index 49c36fb43..c172dbd3a 100644
--- a/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_normal.json
+++ b/projects/forge/src/generated/resources/data/computercraft/recipes/turtle_normal.json
@@ -1,7 +1,6 @@
 {
   "type": "computercraft:turtle",
   "category": "redstone",
-  "family": "normal",
   "key": {
     "#": {"tag": "forge:ingots/iron"},
     "C": {"item": "computercraft:computer_normal"},
diff --git a/projects/forge/src/generated/resources/data/minecraft/tags/blocks/wither_immune.json b/projects/forge/src/generated/resources/data/minecraft/tags/blocks/wither_immune.json
new file mode 100644
index 000000000..e1cc18b5d
--- /dev/null
+++ b/projects/forge/src/generated/resources/data/minecraft/tags/blocks/wither_immune.json
@@ -0,0 +1 @@
+{"values": ["computercraft:computer_command"]}