Multiblocks now use dummy blocks. BaseMultiblockDummyBlock created for all dummies to extend from.

src/main/java/net/xevianlight/aphelion/Aphelion.java

@@ -6,6 +6,7 @@ import net.neoforged.fml.event.lifecycle.FMLClientSetupEvent;
 import net.neoforged.neoforge.client.event.EntityRenderersEvent;
 import net.neoforged.neoforge.client.event.RegisterMenuScreensEvent;
 import net.neoforged.neoforge.client.extensions.common.RegisterClientExtensionsEvent;
+import net.xevianlight.aphelion.block.dummy.renderer.MultiblockDummyRenderer;
 import net.xevianlight.aphelion.client.AphelionConfig;
 import net.xevianlight.aphelion.core.init.*;
 import net.xevianlight.aphelion.fluid.BaseFluidType;
@@ -114,7 +115,7 @@ public class Aphelion {
 
         @SubscribeEvent
         public static void registerBER(EntityRenderersEvent.RegisterRenderers event) {
-
+            event.registerBlockEntityRenderer(ModBlockEntities.VAF_MULTIBLOCK_DUMMY_ENTITY.get(), MultiblockDummyRenderer::new);
         }
 
         @SubscribeEvent

src/main/java/net/xevianlight/aphelion/block/custom/ArcFurnaceCasingBlock.java

@@ -9,6 +9,7 @@ import net.minecraft.world.SimpleMenuProvider;
 import net.minecraft.world.entity.player.Player;
 import net.minecraft.world.item.Item;
 import net.minecraft.world.item.context.BlockPlaceContext;
+import net.minecraft.world.level.BlockGetter;
 import net.minecraft.world.level.Level;
 import net.minecraft.world.level.block.BaseEntityBlock;
 import net.minecraft.world.level.block.Block;
@@ -19,10 +20,11 @@ import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.block.state.StateDefinition;
 import net.minecraft.world.level.block.state.properties.BooleanProperty;
 import net.minecraft.world.phys.BlockHitResult;
+import net.xevianlight.aphelion.block.dummy.BaseMultiblockDummyBlock;
 import net.xevianlight.aphelion.block.entity.custom.EAFPartEntity;
-import net.xevianlight.aphelion.block.entity.custom.ElectricArcFurnaceEntity;
 import net.xevianlight.aphelion.block.entity.custom.VacuumArcFurnaceControllerEntity;
 import net.xevianlight.aphelion.util.AphelionBlockStateProperties;
+import net.xevianlight.aphelion.util.IMultiblockController;
 import net.xevianlight.aphelion.util.MultiblockHelper;
 import org.jetbrains.annotations.Nullable;
 
@@ -44,7 +46,7 @@ public class ArcFurnaceCasingBlock extends BaseEntityBlock {
     public static Properties getProperties() {
         return Properties
                 .of()
-                .sound(SoundType.ANVIL)
+                .sound(SoundType.NETHERITE_BLOCK)
                 .destroyTime(2f)
                 .explosionResistance(10f)
                 .requiresCorrectToolForDrops();
@@ -66,6 +68,12 @@ public class ArcFurnaceCasingBlock extends BaseEntityBlock {
 //        return new EAFPartEntity(blockPos, blockState);
 //    }
 
+    @Override
+    public void onPlace(BlockState state, Level level, BlockPos pos, BlockState oldState, boolean movedByPiston) {
+        super.onPlace(state, level, pos, oldState, movedByPiston);
+        if (!level.isClientSide()) pingNearbyController(level, pos);
+    }
+
     private void pingNearbyController(Level level, BlockPos pos) {
         int r = 5;
         BlockPos.MutableBlockPos mp = new BlockPos.MutableBlockPos();
@@ -75,39 +83,17 @@ public class ArcFurnaceCasingBlock extends BaseEntityBlock {
                 for (int dz=-r; dz<=r; dz++) {
                     mp.set(pos.getX()+dx, pos.getY()+dy, pos.getZ()+dz);
                     BlockEntity be = level.getBlockEntity(mp);
-                    if (be instanceof VacuumArcFurnaceControllerEntity vaf) {
+                    if (be instanceof IMultiblockController controller) {
-                        if (level.getBlockState(vaf.getBlockPos()).getBlock() instanceof VacuumArcFurnaceController) {
+                        controller.markDirty();
-                            MultiblockHelper.tryForm(level, vaf.getBlockState(), vaf.getBlockPos(), VacuumArcFurnaceControllerEntity.SHAPE, AphelionBlockStateProperties.FORMED);
+
-                        }
                     }
                 }
     }
 
-    @Override
-    public InteractionResult useWithoutItem(BlockState state, Level level, BlockPos pos, Player player, BlockHitResult result) {
-        if (state.getValue(AphelionBlockStateProperties.FORMED)) {
-            if (!level.isClientSide && player instanceof ServerPlayer serverPlayer && level.getBlockEntity(pos) instanceof EAFPartEntity eafPartEntity) {
-                if (eafPartEntity.getControllerPos() != null)
-                    if (level.getBlockEntity(eafPartEntity.getControllerPos()) instanceof VacuumArcFurnaceControllerEntity)
-                        serverPlayer.openMenu(new SimpleMenuProvider((VacuumArcFurnaceControllerEntity) level.getBlockEntity(eafPartEntity.getControllerPos()), Component.literal("Vacuum Arc Furnace")), eafPartEntity.getControllerPos());
-            }
-            return InteractionResult.sidedSuccess(level.isClientSide);
-        }
-
-        return InteractionResult.FAIL;
-    }
-
-    @Override
-    public void onPlace(BlockState state, Level level, BlockPos pos, BlockState oldState, boolean movedByPiston) {
-        super.onPlace(state, level, pos, oldState, movedByPiston);
-        if (!level.isClientSide()) pingNearbyController(level, pos);
-    }
-
     @Override
     public void onRemove(BlockState state, Level level, BlockPos pos, BlockState newState, boolean movedByPiston) {
-        if (!level.isClientSide() && state.getBlock() != newState.getBlock()) {
+        if (!level.isClientSide() && state.getBlock() != newState.getBlock())
             pingNearbyController(level, pos);
-        }
         super.onRemove(state, level, pos, newState, movedByPiston);
     }
 

src/main/java/net/xevianlight/aphelion/block/custom/VacuumArcFurnaceController.java

@@ -25,9 +25,11 @@ import net.minecraft.world.level.block.state.properties.BooleanProperty;
 import net.minecraft.world.level.block.state.properties.DirectionProperty;
 import net.minecraft.world.phys.BlockHitResult;
 import net.neoforged.neoforge.items.ItemStackHandler;
+import net.xevianlight.aphelion.block.entity.custom.ElectricArcFurnaceEntity;
 import net.xevianlight.aphelion.block.entity.custom.VacuumArcFurnaceControllerEntity;
 import net.xevianlight.aphelion.core.init.ModBlockEntities;
 import net.xevianlight.aphelion.util.AphelionBlockStateProperties;
+import net.xevianlight.aphelion.util.IMultiblockController;
 import net.xevianlight.aphelion.util.MultiblockHelper;
 import org.jetbrains.annotations.Nullable;
 
@@ -43,6 +45,8 @@ public class VacuumArcFurnaceController extends BaseEntityBlock {
     public VacuumArcFurnaceController(Properties properties) {
         super(properties);
         this.registerDefaultState(this.getStateDefinition().any()
+                .setValue(FACING, Direction.NORTH)
+                .setValue(LIT, false)
                 .setValue(FORMED, false));
     }
 
@@ -61,7 +65,7 @@ public class VacuumArcFurnaceController extends BaseEntityBlock {
     public static Properties getProperties() {
         return Properties
                 .of()
-                .sound(SoundType.METAL)
+                .sound(SoundType.NETHERITE_BLOCK)
                 .destroyTime(2f)
                 .explosionResistance(10f)
                 .requiresCorrectToolForDrops();
@@ -73,7 +77,6 @@ public class VacuumArcFurnaceController extends BaseEntityBlock {
 
     @Override
     public InteractionResult useWithoutItem(BlockState state, Level level, BlockPos pos, Player player, BlockHitResult result) {
-
         if (!level.isClientSide && player instanceof ServerPlayer serverPlayer && level.getBlockEntity(pos) instanceof VacuumArcFurnaceControllerEntity vacuumArcFurnaceEntity) {
             if (vacuumArcFurnaceEntity.isFormed())
                 serverPlayer.openMenu(new SimpleMenuProvider(vacuumArcFurnaceEntity, Component.literal("Vacuum Arc Furnace")), pos);
@@ -110,8 +113,8 @@ public class VacuumArcFurnaceController extends BaseEntityBlock {
         super.onPlace(state, level, pos, oldState, movedByPiston);
         if (!level.isClientSide() && oldState.getBlock() != state.getBlock()) {
             BlockEntity blockEntity= level.getBlockEntity(pos);
-            if (blockEntity instanceof VacuumArcFurnaceControllerEntity vacuumArcFurnaceEntity) {
+            if (blockEntity instanceof IMultiblockController mbController) {
-                MultiblockHelper.tryForm(level, state, pos, vacuumArcFurnaceEntity.SHAPE, AphelionBlockStateProperties.FORMED);
+                mbController.markDirty();
             }
         }
     }

src/main/java/net/xevianlight/aphelion/block/dummy/BaseMultiblockDummyBlock.java

@@ -0,0 +1,173 @@
+package net.xevianlight.aphelion.block.dummy;
+
+import com.mojang.serialization.MapCodec;
+import net.minecraft.core.BlockPos;
+import net.minecraft.network.chat.Component;
+import net.minecraft.server.level.ServerPlayer;
+import net.minecraft.world.InteractionHand;
+import net.minecraft.world.InteractionResult;
+import net.minecraft.world.ItemInteractionResult;
+import net.minecraft.world.SimpleMenuProvider;
+import net.minecraft.world.entity.player.Player;
+import net.minecraft.world.inventory.MenuConstructor;
+import net.minecraft.world.item.Item;
+import net.minecraft.world.item.ItemStack;
+import net.minecraft.world.level.BlockGetter;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.BaseEntityBlock;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.block.RenderShape;
+import net.minecraft.world.level.block.SoundType;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+import net.minecraft.world.phys.BlockHitResult;
+import net.xevianlight.aphelion.util.IMultiblockController;
+import net.xevianlight.aphelion.util.IMultiblockPart;
+import org.jetbrains.annotations.Nullable;
+
+public class BaseMultiblockDummyBlock extends BaseEntityBlock {
+
+    public static final MapCodec<BaseMultiblockDummyBlock> CODEC = simpleCodec(BaseMultiblockDummyBlock::new);
+
+    public BaseMultiblockDummyBlock(Properties properties) {
+        super(properties);
+    }
+
+    @Override
+    protected MapCodec<? extends BaseEntityBlock> codec() {
+        return CODEC;
+    }
+
+    @Override
+    public @Nullable BlockEntity newBlockEntity(BlockPos blockPos, BlockState blockState) {
+        return null;
+    }
+
+    public static Item.Properties getItemProperties() {
+        return new Item.Properties();
+    }
+
+    public static Properties getProperties() {
+        return Properties
+                .of()
+                .sound(SoundType.NETHERITE_BLOCK)
+                .destroyTime(2f)
+                .explosionResistance(10f)
+                .requiresCorrectToolForDrops();
+    }
+
+    @Override
+    protected RenderShape getRenderShape(BlockState state) {
+        return RenderShape.INVISIBLE;
+    }
+
+
+    @Override
+    public int getLightBlock(BlockState state, BlockGetter level, BlockPos pos) {
+        return 0;
+    }
+
+    @Override
+    public boolean propagatesSkylightDown(BlockState state, BlockGetter level, BlockPos pos) {
+        return true;
+    }
+
+    private void pingNearbyController(Level level, BlockPos pos) {
+        int r = 5;
+        BlockPos.MutableBlockPos mp = new BlockPos.MutableBlockPos();
+
+        for (int dx=-r; dx<=r; dx++)
+            for (int dy=-r; dy<=r; dy++)
+                for (int dz=-r; dz<=r; dz++) {
+                    mp.set(pos.getX()+dx, pos.getY()+dy, pos.getZ()+dz);
+                    BlockEntity be = level.getBlockEntity(mp);
+                    if (be instanceof IMultiblockController controller) {
+                            controller.markDirty();
+                    }
+                }
+    }
+
+//    @Override
+//    public InteractionResult useWithoutItem(BlockState state, Level level, BlockPos pos, Player player, BlockHitResult result) {
+//        if (!level.isClientSide && player instanceof ServerPlayer serverPlayer) {
+//            if (level.getBlockEntity(pos) instanceof IMultiblockPart multiblockPartEntity) {
+////            if (multiblockPartEntity.getControllerPos() != null) {
+//                if (level.getBlockEntity(multiblockPartEntity.getControllerPos()) instanceof IMultiblockController controller)
+//                    serverPlayer.openMenu(new SimpleMenuProvider((MenuConstructor) level.getBlockEntity(multiblockPartEntity.getControllerPos()), Component.literal(controller.getMenuTitle())), multiblockPartEntity.getControllerPos());
+////            } else {
+////                if (level.getBlockEntity(pos) instanceof IMultiblockPart mbp) {
+////                    level.setBlock(pos, mbp.getMimicing(), UPDATE_ALL);
+////                } else {
+////                    level.setBlock(pos, Blocks.AIR.defaultBlockState(), UPDATE_ALL);
+////                }
+////            }
+//                return InteractionResult.sidedSuccess(level.isClientSide);
+//            }
+//        }
+//
+//        return InteractionResult.FAIL;
+//    }
+
+
+    @Override
+    public InteractionResult useWithoutItem(BlockState state, Level level, BlockPos pos, Player player, BlockHitResult result) {
+
+        if (!level.isClientSide && player instanceof ServerPlayer serverPlayer) {
+            if (level.getBlockEntity(pos) instanceof IMultiblockPart mbPartEntity) {
+                if (mbPartEntity.getControllerPos() != null) {
+                    if (level.getBlockEntity(mbPartEntity.getControllerPos()) instanceof IMultiblockController controller) {
+                        serverPlayer.openMenu(new SimpleMenuProvider((MenuConstructor) level.getBlockEntity(mbPartEntity.getControllerPos()), Component.literal(controller.getMenuTitle())), mbPartEntity.getControllerPos());
+                        return InteractionResult.sidedSuccess(level.isClientSide);
+                    }
+                } else {
+                    if (level.getBlockEntity(pos) instanceof IMultiblockPart mbp) {
+                        level.setBlock(pos, mbp.getMimicing(), UPDATE_ALL);
+                    } else {
+                        level.setBlock(pos, Blocks.AIR.defaultBlockState(), UPDATE_ALL);
+                    }
+                    return InteractionResult.FAIL;
+                }
+            }
+        }
+        return InteractionResult.FAIL;
+    }
+
+    @Override
+    public ItemInteractionResult useItemOn(ItemStack stack, BlockState state, Level level, BlockPos pos,
+                                           Player player, InteractionHand hand, BlockHitResult hit) {
+        // Always handle dummy interaction, even with an item in hand
+        if (!level.isClientSide && player instanceof ServerPlayer serverPlayer
+                && level.getBlockEntity(pos) instanceof IMultiblockPart part) {
+
+            if (part.getControllerPos() != null) {
+                BlockEntity cbe = level.getBlockEntity(part.getControllerPos());
+                if (cbe instanceof IMultiblockController controller) {
+                    serverPlayer.openMenu(
+                            new SimpleMenuProvider((MenuConstructor) cbe, Component.literal(controller.getMenuTitle())),
+                            part.getControllerPos()
+                    );
+                }
+            } else {
+                level.setBlock(pos, part.getMimicing() != null ? part.getMimicing() : Blocks.AIR.defaultBlockState(), UPDATE_ALL);
+            }
+
+            return ItemInteractionResult.CONSUME; // <- prevents item use/placement
+        }
+
+        return ItemInteractionResult.SUCCESS;
+    }
+
+    @Override
+    protected void onPlace(BlockState state, Level level, BlockPos pos, BlockState oldState, boolean movedByPiston) {
+
+    }
+
+    @Override
+    public void onRemove(BlockState state, Level level, BlockPos pos, BlockState newState, boolean movedByPiston) {
+        if (!level.isClientSide() && state.getBlock() != newState.getBlock()) {
+            if (level.getBlockEntity(pos) instanceof IMultiblockPart mbPart)
+                mbPart.onDummyBroken();
+        }
+//        super.onRemove(state, level, pos, newState, movedByPiston);
+    }
+}

src/main/java/net/xevianlight/aphelion/block/dummy/VAFMultiblockDummyBlock.java

@@ -0,0 +1,18 @@
+package net.xevianlight.aphelion.block.dummy;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.state.BlockState;
+import net.xevianlight.aphelion.block.dummy.entity.VAFMultiblockDummyBlockEntity;
+import org.jetbrains.annotations.Nullable;
+
+public class VAFMultiblockDummyBlock extends BaseMultiblockDummyBlock {
+    public VAFMultiblockDummyBlock(Properties properties) {
+        super(properties);
+    }
+
+    @Override
+    public @Nullable BlockEntity newBlockEntity(BlockPos blockPos, BlockState blockState) {
+        return new VAFMultiblockDummyBlockEntity(blockPos, blockState);
+    }
+}

src/main/java/net/xevianlight/aphelion/block/dummy/entity/BaseMultiblockDummyBlockEntity.java

@@ -0,0 +1,185 @@
+package net.xevianlight.aphelion.block.dummy.entity;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.core.Direction;
+import net.minecraft.core.HolderLookup;
+import net.minecraft.nbt.CompoundTag;
+import net.minecraft.nbt.NbtUtils;
+import net.minecraft.network.protocol.game.ClientboundBlockEntityDataPacket;
+import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.block.entity.BlockEntity;
+import net.minecraft.world.level.block.entity.BlockEntityType;
+import net.minecraft.world.level.block.state.BlockState;
+import net.neoforged.neoforge.energy.IEnergyStorage;
+import net.neoforged.neoforge.items.IItemHandler;
+import net.neoforged.neoforge.items.ItemStackHandler;
+import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.block.entity.energy.ModEnergyStorage;
+import net.xevianlight.aphelion.core.init.ModBlockEntities;
+import net.xevianlight.aphelion.util.IMultiblockController;
+import net.xevianlight.aphelion.util.IMultiblockPart;
+import net.xevianlight.aphelion.util.SidedSlotHandler;
+import org.jetbrains.annotations.Nullable;
+
+public class BaseMultiblockDummyBlockEntity extends BlockEntity implements IMultiblockPart {
+    @Nullable private BlockPos controllerPos;
+    private BlockState mimicing = Blocks.AIR.defaultBlockState();
+
+    @Nullable
+    private ItemStackHandler getControllerInventory() {
+        if (level == null) return null;
+
+        BlockPos cPos = getControllerPos();
+        if (cPos == null) return null;
+
+        BlockEntity be = level.getBlockEntity(cPos);
+        if (be instanceof IMultiblockController controller) {
+            return controller.getInventory();
+        }
+        return null;
+    }
+
+    public IItemHandler getItemHandler(@Nullable Direction direction) {
+        ItemStackHandler inv = getControllerInventory();
+        if (inv == null) return new ItemStackHandler(0); // or null, depending on your needs
+
+        // IMPORTANT: your indices are almost certainly 0..3, not 1..4
+        return new SidedSlotHandler(inv, new int[]{0,1,2,3}, true, true);
+    }
+
+    @Nullable
+    private ModEnergyStorage getControllerEnergy() {
+        if (level == null) return null;
+
+        BlockPos cPos = getControllerPos();
+        if (cPos == null) return null;
+
+        BlockEntity be = level.getBlockEntity(cPos);
+        if (be instanceof IMultiblockController controller) {
+            return controller.getEnergy();
+        }
+        return null;
+    }
+
+    public IEnergyStorage getEnergyStorage(@Nullable Direction direction) {
+        ModEnergyStorage nrg = getControllerEnergy();
+        if (nrg == null) return new ModEnergyStorage(0, 0) {
+            @Override
+            public void onEnergyChanged() {
+
+            }
+        };
+
+        return nrg;
+    }
+
+//    public IEnergyStorage getEnergyStorage(@Nullable Direction direction) {
+//        if (direction == null)
+//            return isFormed() ? ENERGY_STORAGE : NULL_ENERGY_STORAGE;
+//        return isFormed() ? ENERGY_STORAGE : null;
+//    }
+
+    public BaseMultiblockDummyBlockEntity(BlockEntityType<?> type, BlockPos pos, BlockState blockState) {
+        super(type, pos, blockState);
+    }
+
+    public void setControllerPos(@Nullable BlockPos pos) {
+        controllerPos = pos;
+        setChanged();
+        if (level != null) {
+            level.sendBlockUpdated(worldPosition, getBlockState(), getBlockState(), 3);
+            invalidateCapabilities();
+        }
+    }
+
+    public @Nullable BlockPos getControllerPos() {
+        return controllerPos;
+    }
+
+    @Override
+    public void onDummyBroken() {
+        if (level == null || level.isClientSide) return;
+
+        if (controllerPos == null) {
+            level.setBlock(getBlockPos(), getMimicing(), Block.UPDATE_ALL);
+            return;
+        }
+
+        BlockEntity be = level.getBlockEntity(controllerPos);
+        if (be instanceof IMultiblockController controller) {
+            controller.markDirty();
+        }
+    }
+
+    @Override
+    protected void saveAdditional(CompoundTag tag, HolderLookup.Provider registries) {
+        super.saveAdditional(tag, registries);
+        if (controllerPos != null) tag.putLong("controller", controllerPos.asLong());
+        tag.put("mimic", NbtUtils.writeBlockState(mimicing));
+    }
+
+    @Override
+    protected void loadAdditional(CompoundTag tag, HolderLookup.Provider registries) {
+        super.loadAdditional(tag, registries);
+        controllerPos = tag.contains("controller") ? BlockPos.of(tag.getLong("controller")) : null;
+        if (tag.contains("mimic")) {
+            // Depending on your version, this line may need the registry lookup variant.
+            setMimicing(NbtUtils.readBlockState(registries.lookupOrThrow(net.minecraft.core.registries.Registries.BLOCK), tag.getCompound("mimic")));
+        }
+    }
+
+    @Override
+    public void onDataPacket(net.minecraft.network.Connection net,
+                             ClientboundBlockEntityDataPacket pkt,
+                             HolderLookup.Provider registries) {
+
+        CompoundTag tag = pkt.getTag();
+        if (tag != null) {
+            loadAdditional(tag, registries);
+        }
+
+        // Force rerender on client
+        if (level != null) {
+            level.sendBlockUpdated(worldPosition, getBlockState(), getBlockState(), 3);
+            requestModelDataUpdate(); // if you rely on model data
+        }
+    }
+
+    @Override
+    public ClientboundBlockEntityDataPacket getUpdatePacket() {
+        return ClientboundBlockEntityDataPacket.create(this);
+    }
+
+    @Override
+    public CompoundTag getUpdateTag(HolderLookup.Provider registries) {
+        CompoundTag tag = new CompoundTag();
+        saveAdditional(tag, registries);
+        return tag;
+    }
+
+    @Override
+    public void handleUpdateTag(CompoundTag tag, HolderLookup.Provider registries) {
+        loadAdditional(tag, registries);
+
+        // CLIENT: force rerender
+        if (level != null) {
+            level.sendBlockUpdated(worldPosition, getBlockState(), getBlockState(), Block.UPDATE_ALL);
+        }
+    }
+
+    @Override
+    public BlockState getMimicing() {
+        return mimicing;
+    }
+
+    @Override
+    public void setMimicing(BlockState newState) {
+        mimicing = newState;
+        setChanged();
+        if (level != null) {
+            level.sendBlockUpdated(worldPosition, getBlockState(), getBlockState(), 3);
+            requestModelDataUpdate(); // only if you use model data
+        }
+    }
+}

src/main/java/net/xevianlight/aphelion/block/dummy/entity/VAFMultiblockDummyBlockEntity.java

@@ -0,0 +1,12 @@
+package net.xevianlight.aphelion.block.dummy.entity;
+
+import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.block.state.BlockState;
+import net.xevianlight.aphelion.core.init.ModBlockEntities;
+
+public class VAFMultiblockDummyBlockEntity extends BaseMultiblockDummyBlockEntity {
+    public VAFMultiblockDummyBlockEntity(BlockPos pos, BlockState blockState) {
+        super(ModBlockEntities.VAF_MULTIBLOCK_DUMMY_ENTITY.get(), pos, blockState);
+    }
+}

src/main/java/net/xevianlight/aphelion/block/dummy/renderer/MultiblockDummyRenderer.java

@@ -0,0 +1,52 @@
+package net.xevianlight.aphelion.block.dummy.renderer;
+
+import com.mojang.blaze3d.vertex.PoseStack;
+import net.minecraft.client.Minecraft;
+import net.minecraft.client.renderer.LightTexture;
+import net.minecraft.client.renderer.MultiBufferSource;
+import net.minecraft.client.renderer.RenderType;
+import net.minecraft.client.renderer.block.BlockRenderDispatcher;
+import net.minecraft.client.renderer.blockentity.BlockEntityRenderer;
+import net.minecraft.client.renderer.blockentity.BlockEntityRendererProvider;
+import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.Level;
+import net.minecraft.world.level.LightLayer;
+import net.minecraft.world.level.block.Blocks;
+import net.minecraft.world.level.block.state.BlockState;
+import net.neoforged.neoforge.client.model.data.ModelData;
+import net.xevianlight.aphelion.block.dummy.entity.BaseMultiblockDummyBlockEntity;
+import net.xevianlight.aphelion.block.entity.custom.EAFPartEntity;
+
+public class MultiblockDummyRenderer implements BlockEntityRenderer<BaseMultiblockDummyBlockEntity> {
+
+    public MultiblockDummyRenderer(BlockEntityRendererProvider.Context context) {
+
+    }
+
+    @Override
+    public void render(BaseMultiblockDummyBlockEntity be, float partialTick, PoseStack poseStack,
+                       MultiBufferSource buffer, int packedLight, int packedOverlay) {
+
+        Level level = be.getLevel();
+        if (level == null) return;
+
+        BlockState mimic = be.getMimicing();           // <-- use stored state
+        if (mimic == null) return;                     // or default to AIR/stone
+
+        BlockRenderDispatcher brd = Minecraft.getInstance().getBlockRenderer();
+
+        for (RenderType rt : brd.getBlockModel(mimic).getRenderTypes(mimic, level.random, ModelData.EMPTY)) {
+            brd.renderBatched(
+                    mimic,
+                    be.getBlockPos(),
+                    level,
+                    poseStack,
+                    buffer.getBuffer(rt),
+                    false,
+                    level.random,
+                    ModelData.EMPTY,
+                    rt
+            );
+        }
+    }
+}

src/main/java/net/xevianlight/aphelion/block/entity/custom/EAFPartEntity.java

@@ -3,10 +3,13 @@ package net.xevianlight.aphelion.block.entity.custom;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.HolderLookup;
 import net.minecraft.nbt.CompoundTag;
+import net.minecraft.world.level.block.Block;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.minecraft.world.level.block.state.BlockState;
+import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.core.init.ModBlockEntities;
+import net.xevianlight.aphelion.util.IMultiblockController;
 import net.xevianlight.aphelion.util.IMultiblockPart;
 import org.jetbrains.annotations.Nullable;
 
@@ -22,6 +25,21 @@ public class EAFPartEntity extends BlockEntity implements IMultiblockPart {
         setChanged();
     }
 
+    @Override
+    public BlockState getMimicing() {
+        return null;
+    }
+
+    @Override
+    public void setMimicing(BlockState newState) {
+
+    }
+
+    @Override
+    public void onDummyBroken() {
+        Aphelion.LOGGER.error("I SHOULDNT BE CALLED!!!");
+    }
+
     public @Nullable BlockPos getControllerPos() {
         return controllerPos;
     }

src/main/java/net/xevianlight/aphelion/block/entity/custom/VacuumArcFurnaceControllerEntity.java

@@ -61,6 +61,13 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
     public static final int OUTPUT_SLOT = 2;
     public static final int ENERGY_SLOT = 3;
 
+    private boolean dirty = false;
+
+    @Override
+    public String getMenuTitle() {
+        return "Vacuum Arc Furnace";
+    }
+
     public VacuumArcFurnaceControllerEntity(BlockPos pos, BlockState blockState) {
         super(ModBlockEntities.VACUUM_ARC_FURNACE_ENTITY.get(), pos, blockState);
         this.data = new ContainerData() {
@@ -109,6 +116,14 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
 
     public void tick(Level level, BlockPos pos, BlockState blockState) {
 
+        if (dirty) {
+            dirty = false;
+            BlockState current = level.getBlockState(pos);
+            MultiblockHelper.tryForm(level, current, pos, SHAPE, AphelionBlockStateProperties.FORMED);
+        }
+
+        BlockState newBlockState = level.getBlockState(pos);
+
         if (!blockState.getValue(AphelionBlockStateProperties.FORMED))
             return;
 
@@ -120,8 +135,8 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
                 // Recipe detected! We have enough energy to process
                 progress++;
                 useEnergy();
-                level.setBlockAndUpdate(pos, blockState.setValue(ElectricArcFurnace.LIT, true));
+                level.setBlockAndUpdate(pos, newBlockState.setValue(ElectricArcFurnace.LIT, true));
-                setChanged(level, pos, blockState);
+                setChanged(level, pos, newBlockState);
 
                 if (hasCraftingFinished()) {
                     outputBlastingResult(INPUT_SLOT, OUTPUT_SLOT);
@@ -129,14 +144,14 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
                 }
             } else if (hasFurnaceRecipe(INPUT_SLOT) && !hasEnoughEnergyToCraft(MACHINE_ENERGY_COST)) {
                 // Recipe detected but we ran out of power
-                level.setBlockAndUpdate(pos, blockState.setValue(ElectricArcFurnace.LIT, false));
+                level.setBlockAndUpdate(pos, newBlockState.setValue(ElectricArcFurnace.LIT, false));
-                setChanged(level, pos, blockState);
+                setChanged(level, pos, newBlockState);
                 progress = progress > 0 ? progress - 1 : 0;
             } else {
                 // Invalid recipe
                 resetProgress();
-                level.setBlockAndUpdate(pos, blockState.setValue(ElectricArcFurnace.LIT, false));
+                level.setBlockAndUpdate(pos, newBlockState.setValue(ElectricArcFurnace.LIT, false));
-                setChanged(level, pos, blockState);
+                setChanged(level, pos, newBlockState);
             }
         } else {
             // Secondary slot is NOT empty, try alloying recipes
@@ -145,8 +160,8 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
                     // Alloy recipe detected! We have enough energy to process
                     progress++;
                     useEnergy();
-                    level.setBlockAndUpdate(pos, blockState.setValue(ElectricArcFurnace.LIT, true));
+                    level.setBlockAndUpdate(pos, newBlockState.setValue(ElectricArcFurnace.LIT, true));
-                    setChanged(level, pos, blockState);
+                    setChanged(level, pos, newBlockState);
 
                     if (hasCraftingFinished()) {
                         outputAlloyingResult(INPUT_SLOT, SECONDARY_INPUT_SLOT, OUTPUT_SLOT);
@@ -154,15 +169,15 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
                     }
                 } else {
                     // Recipe detected but we ran out of power
-                    level.setBlockAndUpdate(pos, blockState.setValue(ElectricArcFurnace.LIT, false));
+                    level.setBlockAndUpdate(pos, newBlockState.setValue(ElectricArcFurnace.LIT, false));
-                    setChanged(level, pos, blockState);
+                    setChanged(level, pos, newBlockState);
                     progress = progress > 0 ? progress - 1 : 0;
                 }
             } else {
                 // Invalid recipe
                 resetProgress();
-                level.setBlockAndUpdate(pos, blockState.setValue(ElectricArcFurnace.LIT, false));
+                level.setBlockAndUpdate(pos, newBlockState.setValue(ElectricArcFurnace.LIT, false));
-                setChanged(level, pos, blockState);
+                setChanged(level, pos, newBlockState);
             }
         }
 
@@ -328,6 +343,11 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
         return isFormed() ? fullHandler : emptyJeiHandler;
     }
 
+    @Override
+    public ModEnergyStorage getEnergy() {
+        return ENERGY_STORAGE;
+    }
+
     public IEnergyStorage getEnergyStorage(@Nullable Direction direction) {
         if (direction == null)
             return isFormed() ? ENERGY_STORAGE : NULL_ENERGY_STORAGE;
@@ -351,6 +371,7 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
         };
     }
 
+    @Override
     public ItemStackHandler getInventory() {
         return inventory;
     }
@@ -416,15 +437,20 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
         };
     }
 
+    @Override
+    public MultiblockHelper.ShapePart[] getMultiblockShape() {
+        return SHAPE;
+    }
+
     public static final MultiblockHelper.ShapePart[] SHAPE = new MultiblockHelper.ShapePart[] {
 
             //Layer -1
-        new MultiblockHelper.ShapePart(new BlockPos(1,-1,0), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(1,-1,0), s -> s.is(ModBlocks.BLOCK_STEEL)),
         new MultiblockHelper.ShapePart(new BlockPos(1,-1,1), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
-        new MultiblockHelper.ShapePart(new BlockPos(1,-1,2), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(1,-1,2), s -> s.is(ModBlocks.BLOCK_STEEL)),
-        new MultiblockHelper.ShapePart(new BlockPos(-1,-1,0), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(-1,-1,0), s -> s.is(ModBlocks.BLOCK_STEEL)),
         new MultiblockHelper.ShapePart(new BlockPos(-1,-1,1), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
-        new MultiblockHelper.ShapePart(new BlockPos(-1,-1,2), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(-1,-1,2), s -> s.is(ModBlocks.BLOCK_STEEL)),
         new MultiblockHelper.ShapePart(new BlockPos(0,-1,0), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
         new MultiblockHelper.ShapePart(new BlockPos(0,-1,1), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
         new MultiblockHelper.ShapePart(new BlockPos(0,-1,2), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
@@ -441,12 +467,12 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
 
             //Layer 1
 
-        new MultiblockHelper.ShapePart(new BlockPos(1,1,0), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(1,1,0), s -> s.is(ModBlocks.BLOCK_STEEL)),
         new MultiblockHelper.ShapePart(new BlockPos(1,1,1), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
-        new MultiblockHelper.ShapePart(new BlockPos(1,1,2), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(1,1,2), s -> s.is(ModBlocks.BLOCK_STEEL)),
-        new MultiblockHelper.ShapePart(new BlockPos(-1,1,0), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(-1,1,0), s -> s.is(ModBlocks.BLOCK_STEEL)),
         new MultiblockHelper.ShapePart(new BlockPos(-1,1,1), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
-        new MultiblockHelper.ShapePart(new BlockPos(-1,1,2), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
+        new MultiblockHelper.ShapePart(new BlockPos(-1,1,2), s -> s.is(ModBlocks.BLOCK_STEEL)),
         new MultiblockHelper.ShapePart(new BlockPos(0,1,0), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
         new MultiblockHelper.ShapePart(new BlockPos(0,1,1), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
         new MultiblockHelper.ShapePart(new BlockPos(0,1,2), s -> s.is(ModBlocks.ARC_FURNACE_CASING_BLOCK)),
@@ -493,15 +519,12 @@ public class VacuumArcFurnaceControllerEntity extends BlockEntity implements Men
         this.formed = formed;
         invalidateCapabilities();
         if (!formed) {
-            drops();
+//            drops();
         }
     }
 
-    private void setFormedState(boolean value) {
+    @Override
-        BlockState state = getBlockState();
+    public void markDirty() {
-        if (state.hasProperty(ElectricArcFurnace.FORMED) && state.getValue(ElectricArcFurnace.FORMED) != value) {
+        dirty = true;
-            level.setBlock(worldPosition, state.setValue(ElectricArcFurnace.FORMED, value), 3);
-        }
     }
-
 }

src/main/java/net/xevianlight/aphelion/core/init/ModBlockEntities.java

@@ -4,6 +4,7 @@ import net.minecraft.core.registries.BuiltInRegistries;
 import net.minecraft.world.level.block.entity.BlockEntityType;
 import net.neoforged.neoforge.registries.DeferredRegister;
 import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.block.dummy.entity.VAFMultiblockDummyBlockEntity;
 import net.xevianlight.aphelion.block.entity.custom.*;
 
 import java.util.function.Supplier;
@@ -35,4 +36,9 @@ public class ModBlockEntities {
             BLOCK_ENTITIES.register("vacuum_arc_furnace_controller_entity", () -> BlockEntityType.Builder.of(
                     VacuumArcFurnaceControllerEntity::new, ModBlocks.VACUUM_ARC_FURNACE_CONTROLLER.get()).build(null)
             );
+
+    public static final Supplier<BlockEntityType<VAFMultiblockDummyBlockEntity>> VAF_MULTIBLOCK_DUMMY_ENTITY =
+            BLOCK_ENTITIES.register("vaf_multiblock_dummy_entity", () -> BlockEntityType.Builder.of(
+                    VAFMultiblockDummyBlockEntity::new, ModBlocks.VAF_MULTIBLOCK_DUMMY_BLOCK.get()).build(null)
+            );
 }

src/main/java/net/xevianlight/aphelion/core/init/ModBlocks.java

@@ -5,6 +5,7 @@ import net.neoforged.neoforge.registries.DeferredBlock;
 import net.neoforged.neoforge.registries.DeferredRegister;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.block.custom.*;
+import net.xevianlight.aphelion.block.dummy.VAFMultiblockDummyBlock;
 
 public class ModBlocks {
     public static final DeferredRegister.Blocks BLOCKS = DeferredRegister.createBlocks(Aphelion.MOD_ID);
@@ -15,4 +16,5 @@ public class ModBlocks {
     public static final  DeferredBlock<Block> ELECTRIC_ARC_FURNACE = BLOCKS.register("electric_arc_furnace", () -> new ElectricArcFurnace(ElectricArcFurnace.getProperties()));
     public static final  DeferredBlock<Block> ARC_FURNACE_CASING_BLOCK = BLOCKS.register("arc_furnace_casing", () -> new ArcFurnaceCasingBlock(ArcFurnaceCasingBlock.getProperties()));
     public static final  DeferredBlock<Block> VACUUM_ARC_FURNACE_CONTROLLER = BLOCKS.register("vacuum_arc_furnace_controller", () -> new VacuumArcFurnaceController(VacuumArcFurnaceController.getProperties()));
+    public static final  DeferredBlock<Block> VAF_MULTIBLOCK_DUMMY_BLOCK = BLOCKS.register("vaf_dummy_block", () -> new VAFMultiblockDummyBlock(VAFMultiblockDummyBlock.getProperties()));
 }

src/main/java/net/xevianlight/aphelion/core/init/ModItems.java

@@ -7,6 +7,7 @@ import net.neoforged.neoforge.registries.DeferredItem;
 import net.neoforged.neoforge.registries.DeferredRegister;
 import net.xevianlight.aphelion.Aphelion;
 import net.xevianlight.aphelion.block.custom.*;
+import net.xevianlight.aphelion.block.dummy.VAFMultiblockDummyBlock;
 import net.xevianlight.aphelion.item.*;
 
 public class ModItems {
@@ -34,4 +35,5 @@ public static final DeferredItem<Item> MUSIC_DISC_BIT_SHIFT = ITEMS.register("mu
     public static final DeferredItem<BlockItem> BLOCK_STEEL = ITEMS.register("block_steel", () -> new BlockItem(ModBlocks.BLOCK_STEEL.get(), BlockSteel.getItemProperties()));
     public static final DeferredItem<BlockItem> ARC_FURNACE_CASING_BLOCK = ITEMS.register("arc_furnace_casing", () -> new BlockItem(ModBlocks.ARC_FURNACE_CASING_BLOCK.get(), ArcFurnaceCasingBlock.getItemProperties()));
     public static final DeferredItem<BlockItem> VACUUM_ARC_FURNACE_CONTROLLER = ITEMS.register("vacuum_arc_furnace_controller", () -> new BlockItem(ModBlocks.VACUUM_ARC_FURNACE_CONTROLLER.get(), VacuumArcFurnaceController.getItemProperties()));
+//    public static final DeferredItem<BlockItem> VAF_MULTIBLOCK_DUMMY_BLOCK = ITEMS.register("vaf_multiblock_dummy_block", () -> new BlockItem(ModBlocks.VAF_MULTIBLOCK_DUMMY_BLOCK.get(), VAFMultiblockDummyBlock.getItemProperties()));
 }

src/main/java/net/xevianlight/aphelion/event/ModBusEvents.java

@@ -9,6 +9,8 @@ import net.neoforged.neoforge.network.handlers.ClientPayloadHandler;
 import net.neoforged.neoforge.network.registration.HandlerThread;
 import net.neoforged.neoforge.network.registration.PayloadRegistrar;
 import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.block.dummy.entity.BaseMultiblockDummyBlockEntity;
+import net.xevianlight.aphelion.block.dummy.entity.VAFMultiblockDummyBlockEntity;
 import net.xevianlight.aphelion.block.entity.custom.ElectricArcFurnaceEntity;
 import net.xevianlight.aphelion.block.entity.custom.TestBlockEntity;
 import net.xevianlight.aphelion.block.entity.custom.VacuumArcFurnaceControllerEntity;
@@ -25,6 +27,9 @@ public class ModBusEvents {
         event.registerBlockEntity(Capabilities.EnergyStorage.BLOCK, ModBlockEntities.ELECTRIC_ARC_FURNACE_ENTITY.get(), ElectricArcFurnaceEntity::getEnergyStorage);
         event.registerBlockEntity(Capabilities.ItemHandler.BLOCK, ModBlockEntities.VACUUM_ARC_FURNACE_ENTITY.get(), VacuumArcFurnaceControllerEntity::getItemHandler);
         event.registerBlockEntity(Capabilities.EnergyStorage.BLOCK, ModBlockEntities.VACUUM_ARC_FURNACE_ENTITY.get(), VacuumArcFurnaceControllerEntity::getEnergyStorage);
+//        event.registerBlockEntity(Capabilities.ItemHandler.BLOCK, ModBlockEntities.VAF_MULTIBLOCK_DUMMY_ENTITY.get(), VAFMultiblockDummyBlockEntity::getItemHandler);
+        event.registerBlockEntity(Capabilities.ItemHandler.BLOCK, ModBlockEntities.VAF_MULTIBLOCK_DUMMY_ENTITY.get(), BaseMultiblockDummyBlockEntity::getItemHandler);
+        event.registerBlockEntity(Capabilities.EnergyStorage.BLOCK, ModBlockEntities.VAF_MULTIBLOCK_DUMMY_ENTITY.get(), BaseMultiblockDummyBlockEntity::getEnergyStorage);
     }
 
     @SubscribeEvent

src/main/java/net/xevianlight/aphelion/util/IMultiblockController.java

@@ -1,9 +1,27 @@
 package net.xevianlight.aphelion.util;
 
 import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.block.state.BlockState;
+import net.neoforged.neoforge.energy.IEnergyStorage;
+import net.neoforged.neoforge.items.ItemStackHandler;
+import net.xevianlight.aphelion.block.entity.energy.ModEnergyStorage;
 import org.jetbrains.annotations.Nullable;
 
 public interface IMultiblockController {
     boolean isFormed();
     void setFormed(boolean formed);
+
+    void markDirty();
+
+    BlockPos getBlockPos();
+
+    BlockState getBlockState();
+
+    MultiblockHelper.ShapePart[] getMultiblockShape();
+
+    String getMenuTitle();
+
+    ItemStackHandler getInventory();
+
+    ModEnergyStorage getEnergy();
 }

src/main/java/net/xevianlight/aphelion/util/IMultiblockPart.java

@@ -1,10 +1,17 @@
 package net.xevianlight.aphelion.util;
 
 import net.minecraft.core.BlockPos;
+import net.minecraft.world.level.block.state.BlockState;
 import org.jetbrains.annotations.Nullable;
 
 public interface IMultiblockPart {
     @Nullable BlockPos getControllerPos();
 
     void setControllerPos(@Nullable BlockPos pos);
+
+    BlockState getMimicing();
+
+    void setMimicing(BlockState newState);
+
+    void onDummyBroken();
 }

src/main/java/net/xevianlight/aphelion/util/MultiblockHelper.java

@@ -3,11 +3,14 @@ package net.xevianlight.aphelion.util;
 import net.minecraft.core.BlockPos;
 import net.minecraft.core.Direction;
 import net.minecraft.world.level.Level;
+import net.minecraft.world.level.block.Block;
+import net.minecraft.world.level.block.Blocks;
 import net.minecraft.world.level.block.entity.BlockEntity;
 import net.minecraft.world.level.block.state.BlockState;
 import net.minecraft.world.level.block.state.properties.BlockStateProperties;
 import net.minecraft.world.level.block.state.properties.BooleanProperty;
 import net.xevianlight.aphelion.Aphelion;
+import net.xevianlight.aphelion.core.init.ModBlocks;
 import org.jetbrains.annotations.Nullable;
 
 import java.util.ArrayList;
@@ -43,18 +46,29 @@ public class MultiblockHelper {
         };
     }
 
-    private static boolean structureMatches(Level level, BlockState state, BlockPos pos, ShapePart[] shape) {
+    private static BlockState effectiveState(Level level, BlockPos pos) {
+        BlockState state = level.getBlockState(pos);
+
+        if (state.is(ModBlocks.VAF_MULTIBLOCK_DUMMY_BLOCK.get())) {
+            BlockEntity be = level.getBlockEntity(pos);
+            if (be instanceof IMultiblockPart part) {
+                BlockState mimic = part.getMimicing();
+                if (mimic != null) return mimic;
+            }
+        }
+        return state;
+    }
+
+    private static boolean structureMatches(Level level, BlockState controllerState, BlockPos controllerPos, ShapePart[] shape) {
         if (level == null || level.isClientSide) return false;
 
-        Direction facing = state.getValue(BlockStateProperties.HORIZONTAL_FACING);
+        Direction facing = controllerState.getValue(BlockStateProperties.HORIZONTAL_FACING);
 
         for (ShapePart part : shape) {
-            BlockPos testPos = pos.offset(rotateY(part.offset(), facing));
+            BlockPos testPos = controllerPos.offset(rotateY(part.offset(), facing));
-            BlockState check = level.getBlockState(testPos);
+            BlockState check = effectiveState(level, testPos);
 
-            if (!part.rule().test(check)) {
+            if (!part.rule().test(check)) return false;
-                return false;
-            }
         }
         return true;
     }
@@ -70,14 +84,13 @@ public class MultiblockHelper {
         boolean valid = structureMatches(level, state, pos, shape);
 
         if (valid && !controller.isFormed()) {
-            controller.setFormed(true);
             linkParts(level, state, pos, shape, formedProp);
-            if (state.hasProperty(AphelionBlockStateProperties.FORMED) && !state.getValue(AphelionBlockStateProperties.FORMED)) {
+            controller.setFormed(true);
-                level.setBlock(pos, state.setValue(AphelionBlockStateProperties.FORMED, true), 3);
+            setControllerFormedProp(level, pos, true, formedProp);
-            }
         } else if (!valid && controller.isFormed()) {
             unform(level, state, pos, shape, formedProp);
         }
+
     }
 
     public static void unform(Level level, BlockState state, BlockPos pos, ShapePart[] shape, @Nullable BooleanProperty formedProp) {
@@ -87,11 +100,9 @@ public class MultiblockHelper {
         if (!(be instanceof IMultiblockController controller)) return;
 
         controller.setFormed(false);
-        if (state.hasProperty(AphelionBlockStateProperties.FORMED) && state.getValue(AphelionBlockStateProperties.FORMED)) {
+        setControllerFormedProp(level, pos, false, formedProp);
-            level.setBlock(pos, state.setValue(AphelionBlockStateProperties.FORMED, false), 3);
-        }
 
-        unlinkParts(level, state, pos, shape, formedProp);
+        unlinkParts(level, level.getBlockState(pos), pos, shape, formedProp);
 
     }
 
@@ -106,58 +117,64 @@ public class MultiblockHelper {
 
     }
 
-    private static void unlinkParts(Level level, BlockState state, BlockPos pos, ShapePart[] shape, @Nullable BooleanProperty formedProp) {
+    private static void unlinkParts(Level level, BlockState controllerState, BlockPos controllerPos, ShapePart[] shape, @Nullable BooleanProperty formedProp) {
         if (level == null || level.isClientSide) return;
 
-        Direction facing = state.getValue(BlockStateProperties.HORIZONTAL_FACING);
+        Direction facing = controllerState.getValue(BlockStateProperties.HORIZONTAL_FACING);
 
         for (ShapePart part : shape) {
-            BlockPos partPos = pos.offset(rotateY(part.offset(), facing));
+            BlockPos partPos = controllerPos.offset(rotateY(part.offset(), facing));
-            BlockState st = level.getBlockState(partPos);
-
-            if (formedProp != null && st.hasProperty(formedProp) && st.getValue(formedProp)) {
-                level.setBlock(partPos, st.setValue(formedProp, false), 3);
-            }
 
             BlockEntity be = level.getBlockEntity(partPos);
-            if (be instanceof IMultiblockPart mbPart) {
+            if (!(be instanceof IMultiblockPart dummy)) {
-                if (pos.equals(mbPart.getControllerPos())) {
+                // Don't return — just skip this position
-                    mbPart.setControllerPos(null);
+                continue;
-                    be.setChanged();
-                }
             }
-        }
 
+            // Only undo if this dummy belongs to this controller
+            if (!controllerPos.equals(dummy.getControllerPos())) continue;
+
+            BlockState restore = dummy.getMimicing();
+            if (restore == null) restore = Blocks.AIR.defaultBlockState();
+
+            // Restore the original block
+            level.setBlock(partPos, restore, Block.UPDATE_ALL);
+
+            // Clear ownership (not strictly necessary since BE is being removed by setBlock)
+            dummy.setControllerPos(null);
+            be.setChanged();
+        }
     }
 
-    private static void linkParts(Level level, BlockState state, BlockPos pos, ShapePart[] shape, @Nullable BooleanProperty formedProp) {
+    private static void linkParts(Level level, BlockState controllerState, BlockPos controllerPos, ShapePart[] shape, @Nullable BooleanProperty formedProp) {
         if (level == null || level.isClientSide) return;
 
-        Direction facing = state.getValue(BlockStateProperties.HORIZONTAL_FACING);
+        Direction facing = controllerState.getValue(BlockStateProperties.HORIZONTAL_FACING);
 
         for (ShapePart part : shape) {
-            BlockPos partPos = pos.offset(rotateY(part.offset(), facing));
+            BlockPos partPos = controllerPos.offset(rotateY(part.offset(), facing));
-            BlockState st = level.getBlockState(partPos);
 
-            Aphelion.LOGGER.debug("[Multiblock] partPos={} block={} hasFormed={} formedVal={}",
+            // 1) Capture the original state BEFORE replacing
-                    partPos,
+            BlockState original = level.getBlockState(partPos);
-                    st.getBlock(),
-                    (formedProp != null && st.hasProperty(formedProp)),
-                    (formedProp != null && st.hasProperty(formedProp)) ? st.getValue(formedProp) : "n/a"
-            );
 
-            if (formedProp != null && st.hasProperty(formedProp) && !st.getValue(formedProp)) {
+            // Optional: don't replace the controller itself
-                level.setBlock(partPos, st.setValue(formedProp, true), 3);
+            if (partPos.equals(controllerPos)) continue;
-                st = level.getBlockState(partPos);
-            }
 
+            // 2) Replace with dummy block unconditionally
+            level.setBlock(partPos, ModBlocks.VAF_MULTIBLOCK_DUMMY_BLOCK.get().defaultBlockState(), Block.UPDATE_ALL);
+
+            // 3) Now fetch the dummy BE (might be null in edge cases)
             BlockEntity be = level.getBlockEntity(partPos);
-            if (be instanceof IMultiblockPart mbPart) {
+            if (!(be instanceof IMultiblockPart dummy)) {
-                if (!pos.equals(mbPart.getControllerPos())) {
+                // If this happens, your dummy block probably isn't creating its BE
-                    mbPart.setControllerPos(pos);
+                Aphelion.LOGGER.warn("[Multiblock] Dummy BE missing at {}", partPos);
-                    be.setChanged();
+                continue;
-                }
             }
+
+            // 4) Set ownership + mimic state
+            dummy.setControllerPos(controllerPos);
+            dummy.setMimicing(original);
+            be.setChanged();
         }
     }
 
@@ -167,20 +184,23 @@ public class MultiblockHelper {
             BlockPos controllerPos,
             ShapePart[] shape
     ) {
+        if (level == null || level.isClientSide) return false;
+
         Direction facing = controllerState.getValue(BlockStateProperties.HORIZONTAL_FACING);
 
         for (ShapePart part : shape) {
             BlockPos rotated = rotateY(part.offset(), facing);
             BlockPos worldPos = controllerPos.offset(rotated);
+            BlockState check = effectiveState(level, worldPos);
 
             BlockState found = level.getBlockState(worldPos);
 
-            if (!part.rule().test(found)) {
+            if (!part.rule().test(check)) {
                 Aphelion.LOGGER.debug("[Multiblock] FAIL at offset=" + part.offset()
                         + " facing=" + facing
                         + " rotated=" + rotated
                         + " worldPos=" + worldPos
-                        + " found=" + found.getBlock());
+                        + " found=" + check.getBlock());
                 return false;
             }
         }
@@ -189,4 +209,23 @@ public class MultiblockHelper {
         return true;
     }
 
+    private static void setControllerFormedProp(Level level, BlockPos pos, boolean formed, @Nullable BooleanProperty formedProp) {
+        if (formedProp == null) return;
+
+        BlockState cur = level.getBlockState(pos);
+        if (!cur.hasProperty(formedProp)) { return; }
+        if (cur.getValue(formedProp) == formed) { return; }
+
+        BlockState before = level.getBlockState(pos);
+        level.setBlock(pos, cur.setValue(formedProp, formed), Block.UPDATE_ALL);
+        level.sendBlockUpdated(pos, before, level.getBlockState(pos), 3);
+
+        BlockEntity be = level.getBlockEntity(pos);
+        if (be instanceof IMultiblockController controller) {
+            controller.setFormed(formed);
+            be.setChanged();
+        }
+
+    }
+
 }

src/main/resources/assets/aphelion/lang/en_us.json

@@ -2,6 +2,8 @@
   "item.aphelion.test_item": "Test Item",
   "block.aphelion.test_block": "Test Block",
   "block.aphelion.electric_arc_furnace": "Electric Arc Furnace",
+  "block.aphelion.vacuum_arc_furnace_controller": "Vacuum Arc Furnace Controller",
+  "block.aphelion.vaf_dummy_block": "Vacuum Arc Furnace",
 
   "item.aphelion.ingot_steel": "Steel Ingot",
   "block.aphelion.block_steel": "Steel Block",