Add-Ons: Expand Your Core Sets with Modular Terrain

Upgrade Your Tabletop Worlds Without Starting Over

Every DM knows the challenge: building massive, interactive 3D DnD terrain options can take hours—or cost a fortune. You don’t need to buy a whole new set to level up your adventures. Our modular-terrain-add-ons expand your core sets into massive battlefields, portable large setups, and sprawling builds—without extra stress.

Start small with the Goblin Cavern, the entry-level Caverns Series set, then grow your world with Rock Bridges, Summoner’s Kit, Dark Pine Forest, Cavern Dirt Ramps, and Special Cavern Walls. Each piece adds depth to your story, gives your DM skills room to grow, and keeps your tabletop modular, paintable, and fully customizable.

Shop Modular Terrain Add-Ons

Build Anything with Modular, Compatible Pieces

Our add-ons aren’t just extra scenery—they’re tools to elevate your campaign. Whether you want to craft custom game boards, multisession dungeon crawls, or multisession castle crawls, these modular systems give you the freedom to design your table your way. All pieces are fully compatible with core sets, easy to store as flat pack DnD terrain, and perfect for portable quick setup for DMs.

Goblin Cavern – ideal for new DMs
Org Cavern – for more advanced encounters
Troll Cavern – create epic monster-filled battles
Dragon’s Lair – high-stakes adventures for experienced players

Every piece features injection-molded terrain, paintable details, realistic textures, and interchangeable trees, making them ideal for modular gaming terrain setups.

Expand Your Caverns Series with Signature Scenery Pieces

Take your tabletop RPG adventures to the next level with signature expansions for the Caverns Series. Add Rock Bridges for dramatic pathways, Summoner’s Kit to challenge your players, Dark Pine Forest for immersive scenery, Cavern Dirt Ramps for vertical encounters, and Special Cavern Walls to create unique dungeon layouts. Each piece is modular, compatible, and designed for durable, reusable gameplay, allowing you to craft sprawling builds, multisession dungeon crawls, and multi-level castle encounters. These expansions are perfect gifts for DMs who want to personalize campaigns with their own creativity.

Featured Dirt Cheap Dungeon Products:

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Why Modular Terrain Add-Ons Are the DM’s Secret Weapon

Durable & Reusable: Injection-molded construction lasts for years of gameplay.
Quick Setup: Snap-on modular pieces save time while supporting portable large setups.
Customizable: Paintable surfaces and interchangeable trees allow full personalization.
Expandable: Combine with core sets, other Cavern Series sets, or build a custom game board.
Eco-Friendly: 30% pre-consumer recycled materials + natural fibers.
Storytelling Boost: Supports sprawling builds, multisession dungeon crawls, and multisession castle adventures.
Great Gifts: Perfect for DMs at any level—affordable, creative, and ready for personal touches.