Tutorials that you're using are outdated. You should use registry events now.   Complicated things simple: Items must be registered inside RegistryEvent.Register<IForgeRegistryEntry> with event::getRegistry()::register() public static void registerItems(RegistryEvent.Register<Item> event) { event.getRegistry().register(item); }   Models must be registered inside ModelRegistryEvent with ModelLoader::setCustomResourceLocation() public static v