Three new worlds in one night

On the evening of 20 October I listed the maze worlds we had and asked the agents for three more: "Let's first talk together about what those 3 could be."

The atlas already held about forty places nobody had built, and the root agent picked three that would each move differently. The Drowned Abbey of Saint Brannoc, where you raise and lower the water to change the maze. Gobblestone Hall, where you are mouse-sized in a sleeping giant's kitchen. And Cinderdeep, the Makers' green-bronze halls under the mine, where rings of wall turn round a hub.

The abbey's nave at high water: the one straight run, as the plan put it, "because the builders made it straight".

"Movement. Emotion"

"Let's build those first 3 above." Then I tried to say what I wanted. "If we can help it, let's not just work on a rectangular grid, but let's work on more authentic interesting routes and paths and objects." Things should be placed "as though they had a purpose originally... if we can answer that it goes in." I asked for "AAA quality within our games feel and current artwork strategy", and finished with two words: "Movement. Emotion".

Music was mine to make. The agent wrote Suno prompts for six pieces, two per world, and warned that free-plan songs are non-commercial. "I pay for Suno." Six songs, The Giant's Snore and The Ancient Machine among them, were in the game within minutes.

One last note before I went: "For the curved layout engine, I mean it can be any shape, different angles of bends, not perfectly circular, jutted routes, angled paths etc." Then: "I am now AFK, as before, let's go."

The night shift

The plan turned that into a design bar every reviewer checked. Each world needs at least four moments where the place answers the hero, and a visit has a shape, ending, in the plan's words, with an exit that "feels like coming up for air".

First came a shared foundation. Walkable space is now drawn as shapes in metres (arcs, rings, paths that pinch and swell, edges roughened with noise) and turned into the grid that sight, chasing and the map already understand. Walls can change during play, and there are hazards, platforms that carry the hero (the abbey's eel punt), climb points, wading and a meter for each world's own pressure.

Under the hood The layout engine alone took three Codex fix rounds to pass, each counterexample becoming a test. The whole piece spent 1,246 of the 1,500 Meshy credits I allowed and about US$2.43 of US$10 of OpenAI.

Three owners then built a world each in parallel, and an independent verifier played all three end to end, in both views and on a phone: two failures first time, then eight of eight. The worlds landed on main in the early hours.

Gobblestone Hall as it landed overnight. The hero is the speck on the boards below the table.

Cinderdeep's Ring Hall: turn the rings until the doorways line up from rim to hub.

Playing them

The next morning: "I had three separate agents doing lots of work last night on this game, and they've all come back, finished, and merged into main." Then I played them.

Gobblestone first. "When I went into Gobblestone Hall, although I like the premise, it's not thought through enough. In all honesty, I pushed the little reel to distract the cat, and then I wandered around everywhere and didn't know what to do." The cat caught me without my noticing: "I didn't really know that I'd been pounced on. Can we do a slow-mo like kill cam of when the cat pounces on you...?" And the mouse holes were too shallow: "If you think about how a rat would have to hide from a cat, it would have to go a lot further into the wall."

Some of it was simply broken. "This spiderweb is rubbish." In the abbey: "There's these weird floating cones. I'm guessing are they meant to be fish or something?" And "Every time I fight this choir knight, the game crashes."

Two of my screenshots from that morning: Gobblestone's web, and the abbey's "fish".

But the abbey had moments. Of Saint Brannoc's floor mosaic: "I really really like this." I wanted more ceremony, though: "a really old tattered hanging piece of cloth, like a flag or something. Obviously it would have got wet at some point."

In Cinderdeep, "The rings are really nice", but a broken seal "is super super thin. It needs structure and weight to it." And the verdict that mattered: "I don't think I can currently complete this Cinderdeep world."

I asked for each item to be treated as a symptom: "Does it actually make sense in the real world? Like, could X be next to Y? Would the rat holes be that shallow?"

Round one: what was really wrong

Cinderdeep could be finished all along: two pulls of the middle ring line the doorways up. You just could not see what a pull did. Each ring's two levers now stand together with a plaque naming the ring.

Under the hood The Hall Sentinel kept vanishing because every prop, even a knee-high mine cart, blocked sight like a full-height wall. Of 41,022 pairs of points a metre apart in the upper hall, 6,979 could not see each other; after the fix, none.

In the abbey, the main outline was traced the opposite way to what the wall builder expected, so about 290 metres of wall had been built as 5 cm slabs: the see-through blocks and paper-thin stair guards in one mistake. The cones became Meshy perch that stay in the water and drain with it, and a tattered banner and a fallen monk went in.

Gobblestone got a cat with a brain. He watches the crumbs where the mice run, turns towards noise, chases at a pace a child can escape, and his pounce plays slowed down from beside the hero.

The pounce, slowed and told, so you know it happened.

I had also said Gobblestone's walls were "bare and kind of perfect", so its owner built surface wear (damp, cracks, scuffs, soot) once, as a kit piece any world can use.

The hearth corner as it landed overnight: bare walls and the mice's trail as a painted ribbon.

Same view, after two rounds: plaster and soot, a log basket, real crumbs, and Sir Pounce moved to watch them.

Round two

Root then sent a checker to play all three on the merged main. All three could be finished, but it found seven new problems. The abbey's objective said "Find your way through the drowned abbey" from start to finish, and Cinderdeep's levers said "sunwise" and "widdershins", words that, in the checker's report, "a child won't know". So the abbey and Cinderdeep got step-by-step objectives like Gobblestone's, the levers now say left and right, and a hero hiding under Gobblestone's bench glows through it. Round two was merged by lunchtime.

What I took from it

One night was enough to build three places where, as the plan asked, every object could answer "why is it there?". What the design bar did not cover was a player in a beautiful room with nothing telling them where to go. Every review passed that. A goal you can read beats a better cat.

There was a bigger gap too. That same morning I opened the quest ledger and saw it: "Right now I can't see that any of those are in this kind of playable quest." Three new worlds, and no story yet that leads you to them.

Brackenmere has three new maze worlds, built in one night. In the Drowned Abbey you raise and lower the water to change the way through. In Gobblestone Hall you are mouse-sized in a sleeping giant's kitchen, keeping out of the cat's way. And in Cinderdeep, deep under the mine, rings of wall turn round a middle until the doorways line up.

The Drowned Abbey at high water, with the old floor picture under the surface.

"Movement. Emotion"

I asked my AI helpers for three worlds that would each feel different to move through. No square grids: winding paths, and every object placed as though it had a reason to be there. My last words were "Movement. Emotion". I made six pieces of music for them, two per world, then went to bed.

Overnight

First the helpers built things every new world could use: curved paths, walls that change while you play, a punt to carry you across water. Then three helpers built one world each, side by side, and another played all three from start to finish. By the early hours they were in the game.

Gobblestone Hall. The hero is the tiny speck on the floor below the table.

Cinderdeep: turn the rings until the doorways line up from the edge to the middle.

Playing them

The next morning I played them, and it wasn't all good.

• In Gobblestone Hall I wandered about and didn't know what to do. The cat caught me and I didn't even notice. And the mouse holes were far too shallow for a mouse to hide in.
• Some things were simply broken: a rubbish spider web, odd floating cones in the abbey (they were meant to be fish), and the game crashed every time I fought one knight.
• In Cinderdeep the rings were lovely, but I didn't think I could finish it.

Two of my screenshots that morning: the spider web, and the abbey's "fish".

The abbey had moments though. I really loved the old floor picture.

What was really wrong

Cinderdeep could be finished all along. You just couldn't see what each lever did. Now each ring's levers stand together with a sign naming the ring. In the abbey, one mistake had built many walls paper thin. The fish now swim in the water, and an old tattered banner hangs on the wall.

The cat got a brain. He watches the crumbs where the mice run, turns towards noises, chases at a speed a child can escape, and when he pounces it plays in slow motion so you know it happened. The bare kitchen walls got damp, cracks and soot.

The cat's pounce, slowed down and told, so you know it happened.

The kitchen corner as it first arrived: bare walls and a painted stripe for the mice's trail.

The same corner afterwards: plaster and soot, a log basket, real crumbs, and the cat watching them.

A second play-through found goals that never changed and lever words a child wouldn't know. Now the goals come step by step, and the levers just say left and right.

What I learned

One night was enough to build three places where every object has a reason to be there. What nobody had checked was a player standing in a beautiful room with no idea where to go. A goal you can read beats a cleverer cat. And there was a bigger gap: three new worlds, and no story yet to lead you to them.