Labyrinth of Ur: AI-Built 3D Dungeon Crawler for the C64

It has been a while since a proper first-person dungeon crawler crossed our desk from the Commodore 64 scene. So when Labyrinth of Ur showed up, with its grid-based corridors and a lone hero clutching a sword, it got my attention fast.

The game comes from a developer going by Ursimon. It wears its influences openly: Dungeon Master and Eye of the Beholder are named as the inspiration. Anyone who has spent a few late nights mapping corridors on graph paper will know exactly what kind of game this is trying to be.

There is a twist in how it was made, though. Labyrinth of Ur was written from scratch in C, and Ursimon built it with the help of AI. That detail will spark some debate, and we will come back to it.

Down the Stairs With Lance

The hero here is Lance, a solitary warrior with no party to back him up. That alone sets it apart from the games it draws on, which leaned heavily on managing a group of adventurers. Here, it is just you and one sword.

Lance's job is to work his way down through seven floors. These are procedurally generated, which means the layouts are assembled by the game itself rather than hand-built level by level. In practice, that should keep each descent from feeling identical to the last.

According to the description, the floors vary a lot in shape and scale. Some are tight, twisting chambers that feel like a proper maze. Others open up into huge halls that loom over you. On a machine with the C64's limits, that kind of range is worth pointing out.

Keys, Potions and Piles of Gold

The structure is classic crawler fare, and I mean that in a good way. Colored keys are scattered around each floor. Find them and you can open the matching doors, which are described as heavily guarded. So grabbing a key is only half the job - you still have to fight your way through whatever sits behind it.

Healing potions are the other thing you will be hunting for. With only one character and no healer in the party, every potion matters. I can already picture myself backing slowly away from a fight, counting bottles.

Then there is the gold. Hoards of it are tucked away in the depths, and collecting them pushes up your final rank on the victory screen. It is a simple idea, but it gives the game a reason to poke into every side room rather than sprinting for the exit. Greedy players, this one is for you.

Built for a Stock Machine

One technical point stands out. Labyrinth of Ur targets unexpanded PAL machines. For newer readers, PAL refers to the TV and video standard used across much of Europe and other regions, and C64 hardware was sold in PAL and NTSC versions with slightly different timing. "Unexpanded" means the game runs on a standard machine, without extra memory or add-on hardware.

That matters. A first-person 3D view is hard work for a home computer from the early eighties. Squeezing it onto stock hardware, written in C rather than hand-tuned assembly, is an ambitious goal. We have seen some wild 3D experiments on the platform lately, like the DOOM64 demake for the C64, and this sits nicely alongside them in spirit, even if the genre is a lot slower and more deliberate.

The AI Question

Now, the elephant in the dungeon. Ursimon openly states that AI helped build the game. Some players will shrug. Others will feel strongly about it. Both reactions are fair.

What I can say is that the source material does not go into detail about how much of the work the AI did, or which parts. So I am not going to guess. The finished design - seven floors, keys, guarded doors, potions, gold and a final score - reads like a coherent, focused take on the genre either way.

Food for Thought

Labyrinth of Ur is part of a pattern we keep running into. Only last week we covered an AI-coded OutRun port for the Amstrad CPC, and now a C64 crawler arrives with a similar story. This suggests AI tools are becoming a regular part of how some hobbyist developers approach old hardware, especially when working in a higher-level language like C.

For players, the interesting part is what that could unlock. If these tools help solo developers tackle genres that once needed a lot of time and expertise, we may see more ambitious projects on 8-bit machines. Whether they hold up in feel and polish against hand-crafted work is still an open question.

Fans of the genre also have other options right now, such as the torchlit Greed & Darkness demo on PC. For Labyrinth of Ur, it is worth watching how the C64 community responds, both to the gameplay and to the way it was made.