Alex's Mobs · Fabric 1.21.11 Port

Alex's Mobs is the most extensive creature-addition mod for Minecraft, featuring over 80 unique mobs ranging from grizzly bears and tigers to cosmic whales and void worms. This is a complete port of Alexthe666's NeoForge implementation to the Fabric modloader targeting 1.21.11, maintaining feature parity including all animations, AI behaviors, custom blocks, and integration with Just Enough Items (JEI).

The port architecture replaces NeoForge's registry and networking systems with Fabric equivalents. A custom AMDeferredRegister shim wraps Fabric registries to preserve the lazy-registration semantics needed by the original code. Networking migrated from @SubscribeEvent handlers to Fabric's PayloadTypeRegistry and ServerLifecycleEvents callbacks. Client rendering—60+ entity renderers plus custom particle effects—adapted from Minecraft's GuiGraphics and DeltaTracker APIs. The Citadel dependency (a separate Fabric port) provides the underlying animation and model framework that all creatures depend on.

Building involved systematic porting of ~778 Java files from NeoForge conventions to Fabric's class structure and method signatures. Tools: Gradle with Loom (official Minecraft mappings), Docker for hermetic builds, and a scripted error-parsing workflow to drive bulk multi-agent corrections. Development was snapshot-based: full recompile after each wave of changes, parse error inventory, dispatch agents to fix patterns in parallel. The mod is packaged as a single 26.4 MB JAR and loads server-side and client-side on vanilla Fabric servers.