Collection: Castle Expansion MOC Building Sets | Compatible with LEGO

Expand your LEGO Castle with custom Castle Expansion MOC sets. Build walls, towers, bridges & gates using LEGO-compatible bricks. Perfect for medieval MOC builders, collectors, and fantasy diorama creators.

27 products

Upgrade Your LEGO Castle with Custom Expansion MOC Sets

Take your medieval builds to the next level with our Castle Expansion MOC Building Sets, expertly designed to be fully compatible with LEGO bricks. Whether you're expanding an existing LEGO castle or building an entire fortress from scratch, these MOC kits offer detailed wall sections, gates, towers, bridges, and more.

Seamless Compatibility with LEGO Bricks

Every Castle Expansion MOC set is built using LEGO-compatible pieces, allowing easy integration with official LEGO Castle sets. Whether you're building a sprawling kingdom or enhancing a small outpost, these expansion sets provide the flexibility to connect, stack, and customize with total freedom—perfect for collectors and builders alike.

Expand Walls, Gates & Defensive Towers

Reinforce your LEGO medieval kingdom with advanced defensive structures including modular walls, archer towers, moats, and fortified gates. These sets let you scale up your castle layout while maintaining authentic medieval design. Build higher, wider, and more secure—ideal for battle scenes or castle displays.

Perfect for Dioramas, Stop-Motion & Roleplay

These expansion sets aren't just for static displays—they're ideal for dynamic storytelling. Use them to create medieval dioramas, stop-motion scenes, or as backdrops for fantasy tabletop games like D&D. Their modularity allows you to rebuild and reimagine your castle over and over again.