The Ultimate Lego Dungeon Terrain
Grids Out, Zones In
When I started using LEGO to build terrain for TTRPGs, I wanted something modular, customizable, and reusable—terrain pieces that could easily swap in and out without being locked into a single setup for a session. LEGO offered a fun, paint-free alternative to traditional minis. Using Technic to connect modular terrain elements was a natural choice, so I built on the classic MILS (Modular Integrated Landscaping System) design. I called my version MITs (Modular Integrated Terrain)—a clever twist, I thought.
Initially, I used a 4x4 stud grid (instead of 3x3) because it felt more in scale with minifigs. Since I wasn’t tied to preexisting 1-inch grids or maps, I had freedom to create what worked for me. My first iteration, MITs 1.0, used a checkerboard pattern to highlight the grid, but this was limiting. Every scene change required either entirely new boards or reusing the same one for everything. On top of that, using four jumper tiles per grid square was producing way too much grip. I needed something a little more maleable. This prompted me to experiment with other designs.
After months of trial and error, I developed MITs 3.0: a fully modular system with layered terrain. It could easily be configured into roads, streams, dungeons, forests, mountains, the underdark, and more! Essentially, it was a system of building blocks made from LEGO building blocks. I kept refining it and was about to place a large order for more bricks—until I saw a video by Professor DM that changed my perspective: grids aren’t necessary; it's okay to be abstract.
After watching that video, I canceled an order for extra parts for a MITs 3.0 map expansion I'd been working on. I no longer needed it. I don't see myself using MITs 3.0, as much as I love it, now that I know that something like UDT exists. I can spend less money on making maps and get more mileage out of what I already have.
For me, the essence of TTRPGs is the freedom to tell stories and make choices that no video game designer could anticipate. While a social contract between the GM and players establishes the game’s boundaries, the beauty of TTRPGs lies in improvisation and creativity.
Grids, however, often disrupt that flow. They impose restrictions on movement and decision-making, turning a TTRPG into a tactical war game. For instance, debates over whether a sleet storm spell hits friendly targets can bog down the narrative. Instead, why not consider whether the character casting it would care about collateral damage? By shifting the focus from rigid rules to roleplay and intent, you keep the story central.
Sure, grids have their place, and for some people that's a deal breaker. I get it. It's just not the game I want to focus on. Zoned combat using the Ultimate Dungeon Terrain concept offers all the flexibility you need to have a great adventure with some cool visuals and creative story telling. So let's get to it!
How It Works
Zoned combat at my table is based on four zones:
- Melee Zone (Center)
Everything in this area is within melee range of one another. - Ranged Zone (Second Ring)
This zone surrounds the melee zone and represents everything within range of the action or other ranged combatants. - Out of Range but in Sight (Raised Platform)
A larger zone that can include small buildings, trees, or walls for flair. It also doubles as a space for unused elements like NPCs, reminders (e.g., unopened chests), or even the DM screen - if you make it part of the back droo. - Out of Sight (Lower Levels)
This zone represents anything completely out of sight. It can serve as a place for "¹off-screen" NPCs, split-party members, or hidden areas the players might revisit later. - Optional: Water Zone
If the environment demands it, you can add a separate water addition to distinguish whether characters or props are submerged.Moving Between Zones
Movement between zones is simple
- Moving one zone costs standard movement points.
- Crossing two zones requires dashing and forfeiting an action.
This approach keeps combat intuitive without rigid measurements, relying on the GM’s descriptions and players’ imaginations to fill in the details. You can still add columns, rocks, ruined walls, or whatever props you need to add flavor.
If this feels oversimplified or overly complicated, don’t worry! This approach relies heavily on the GM’s ability to use Theater of the Mind—something most TTRPGs already incorporate. The method is designed to be simple; there’s no need to reinvent the wheel when everyone already knows what wheels look like. Players naturally abstract walls, ceilings, and background details during play. As GMs, we sometimes underestimate our players and try to define everything, which can inadvertently take away their agency. By leaving certain elements abstract, we challenge players to fill in the gaps, often creating ideas and details we hadn’t even considered during planning.
Example
Both images above show the same fight. One uses the traditional grid-based method, while the other employs UDT. In the traditional version, the boss, the Nightmare King, stands on a platform, observing from a distance as his minions attack the party. The party must survive the minions before reaching the Nightmare King. They progress down the map to defeat the boss and claim the pot of gold.
In UDT, the fight plays out the same but takes less time to resolve. The minions and melee characters battle in the central zone, while ranged party members attack from the ranged zone. As in the previous example, the Nightmare King and his lieutenant remain in a zone out of range but still in sight. Once the party defeats the NPCs, the Nightmare King joins the fray, with the boss fight primarily taking place in the center. A pillar mechanic forces players to spend movement points to take cover—or face the attack head-on.
As Professor DM aptly puts it, "The action in the center plays out like a scene on a stage." That’s the essence of this system. As a GM, you’re setting up scenes, letting players roleplay, and shaping the story. Dungeon walls and grids aren’t necessary—you just need vivid narration to set the tone, leaving the rest to the players’ imaginations.
Modularity
One of my favorite aspects of the "box" approach to the LEGO Ultimate Dungeon Terrain (UDT) concept is that everything you need for a game can be stored inside the board itself. As a GM who often travels to players’ homes or public spaces, bringing my LEGO setup can be cumbersome. But with LEGO UDT, it’s easy! In fact, I could bring just the box if I wanted to. You don’t necessarily need the outer rings—you can use the table surface to represent areas "out of sight" and rely on the melee and ranged zones built into the box itself.
For flexibility, I added Technic bricks around the base so I can attach additional terrain pieces, such as the outer ring or a "proscenium"—a term borrowed from theater for the part of the stage extending beyond its usual boundaries. These attachment points can also be used for modular components, such as a DM screen, as shown in some of the accompanying images.
In my initial design (which you’ll see in the photos), I used 2x2 jumper tiles for the entire board. However, I found they provided too much grip, making it difficult to quickly place or move pieces. This is why I abandoned that approach in version 1.0. In the version presented here, created using BrickLink’s Studio software, I strategically placed jumper tiles only in key spots where props would likely be attached. The remaining surface is smoothed out with regular 2x2 tiles, creating a better balance between grip and functionality.
Simplicity is Key
Using LEGO in a TTRPG game can feel like a complicated endeavor—fun, but undeniably complex. I doubt I’m alone in this sentiment. It’s safe to say LEGO likely won’t release official terrain or guides for integrating their products into TTRPGs anytime soon. This year is unique, thanks to a special 50th-anniversary collaboration with Hasbro, which includes limited-edition Dungeons & Dragons merchandise. Unfortunately, that’s the exception, not the rule. That’s where resources like this site come in—to help bridge the gap and provide inspiration for your table.
To get started, all you need is a bit of imagination and some props. Minifigures make a great starting point. From there, you can add simple elements like ruined walls, columns, and doorways. Trees—like the cone-shaped ones—are easy additions that work well. Treasure chests, barrels, and tables can add flavor, but they aren’t strictly necessary. With UDT, you probably need fewer props than you think. A handful of well-placed elements can make a scene come to life.
Above all, keep it fun! With LEGO UDT, you don’t need to continuously collect more parts to expand your map or worry about running out of space. You’re not limited by table size, piece availability, or arguments over movement points and area-of-effect spells. Instead, you can focus on the story, roleplay, and creating a great adventure. And that’s what matters most.
