must be one vs Illusion Corridor

must be one is a number puzzle built on a single rule — the one in its name. A grid of numbers. Four operators. Combine neighboring tiles with arithmetic and collapse the whole board down to a single 1. That's the entire game: all becomes one. It reads as obvious for about three moves. Then it doesn't. - One rule, no filler — no twenty-minute tutorial, no menus to dig through. You understand it in seconds and spend the rest of your time actually thinking. - Always solvable — every stage is generated so that a solution is guaranteed to exist before you ever see it. If you're stuck, that's on you, not the board. - A climb that keeps widening — early stages stay in single digits; later ones open the range up and the arithmetic gets meaner. - Free, and quick to pick up. One stage on the train; look up an hour later. From office-canard — a one-person studio making small, system-first games. If this one gets its hooks in, there are more small games where it came from.

Illusion Corridor is a quiet isometric puzzle game about perspective. Height and distance cannot always be trusted. Rotate golden mechanisms, slide platforms, raise towers, and align paths that should never meet. When the eye believes, an impossible road appears. Seven chapters and 65 handcrafted levels: - A measured journey from intuitive puzzles to concealed mechanisms, linked axes, and three-character cooperation - Rotating bridges, sliding platforms, lifts, hidden doors, crumbling tiles, and night watchers - No ads, energy systems, loot boxes, or subscriptions - Play all 10 levels of Chapter One plus four later chapter previews for free - One purchase permanently unlocks the remaining 51 levels - Fully offline, with no personal data collection - English, Simplified Chinese, and Japanese Enter the lone tower, cross the court of mechanisms, and walk through the long night until every impossible path becomes one.