Unit 0770 cannot turn left any more. He is due to be scrapped at eight in the morning, and he cannot get to the desk by himself. So they have given him to you. Lay the road in front of him, one square at a time.
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APP PREVIEW
One night in Bo City
App preview · 0:28 · VerticalA terminal line from dispatch, seventy-two orders, and a robot who only goes straight or right. Straight from the game, with no captions added.
App Store pageTHE ONE RULE UNIT 0770
Straight, right, never left
That is all Otto knows. It is also all you need to send him anywhere in the city.
Straight if he can
Where there is road ahead, he takes it. He never stops to think about it.
Right if he cannot
No road ahead, he turns right. He will circle a block to get where he is going.
Never left
His left steering failed. A road that asks him to turn left is a road he cannot take.
You lay the road
Tap to lay a tile or knock out a loose plank, then send him. Fewest tiles and fewest steps are not always the same plan.
What it does
Things that change
Glass that breaks behind him. Belts that carry him, and buttons that turn them. Streets with no lamps, where you see only what his light has touched.
A night in Bo City
Twelve districts from eight in the evening to eight in the morning, in the rain. After the eleventh, the road forks.
After the night
A new map for everyone every Monday, a tower of roads against the clock, and shells for Otto, each with the poster of a film he never made.
CASE STUDY
Behind the work
A puzzle with one rule, and a story that hides inside it.
Most path puzzles let you steer. Otto Was Right takes the steering away: the only thing you control is the road, and the robot obeys one rule you can read in a second. Seventy-two roads had to stay surprising under that rule without ever becoming a maze of guesswork.
Game rules, level search, story and script, art direction, Unity engineering, Blender asset pipeline, sound, store materials, and release.
Independent. Designed, built, and shipped solo.
02Key decisions
- One rule for the robot, so every puzzle is about the road, not the controls.
- Every road was found by an offline search and proven by an exhaustive solver.
- Three ticks per delivery: delivered, fewest tiles, fewest steps. The last two pull apart.
- The story is told in the margins: order notes, a dispatcher’s lines, and a fork at the end.
03Limits & misses
- Roads a player could read at a glance were remade: 25 of them in one late pass.
- The story stills, shell posters and music were made with AI tools from my prompts and direction.
- Offline by design: no account, no ads, no data collected.
04Results
- Released on the App Store on October 29, 2026.
- Twelve districts, seventy-two roads, two endings, and a weekly map on Game Center.
- Forty-odd shells to earn by playing. Nothing to buy.
05What I built
- The road rules, autopilot, level search and solver in pure C#.
- Bo City in Unity 6: twelve districts built through a Blender pipeline, in the rain.
- The film-titles interface, the sound set, the trailer, and every store asset.