PROVEN

Every level in this game was generated by a computer — and then proved correct by two more, written to disagree with the first.

Most generated puzzle packs ask you to trust them. This one doesn't.

Every level here was built backwards from its own solved position, one pull at a time. A level made that way cannot be unsolvable — the solution is the path the generator walked to create it.

Then every level was thrown away and re-proved from scratch. An independent forward search, which knows nothing about how the level was made, finds the shortest possible sequence of pushes. Its answer had to match the generator exactly, or the level was discarded. The solution it produced was then replayed on a third, deliberately naive simulator that shares no code with either search. 

So the number next to each level is not a difficulty rating somebody eyeballed. It is the proven minimum. Match it and the game tells you: you didn't just solve it, you solved it optimally. 120 levels across four tiers, from 6 pushes to 41.

Free, in your browser, no account, no install, nothing uploaded anywhere.

CONTROLS

Arrow keys, WASD or HJKL to move · Z or Backspace to undo, unlimited · R to restart · N and P to change level · swipe or on-screen pad on mobile

DON'T TRUST ME, CHECK IT

A free sample is attached to this page: 16 of the levels as data, their solutions, and verify.py — a checker that re-derives every minimum from scratch and shares no code with the generator. Python 3, no dependencies, no network. Two implementations written apart agreeing is evidence; one agreeing with itself is not.

THE CREATOR PACK

If you're building something, the full level data is available separately: 

levels.json, the .sok/XSB collection every box-pusher engine already reads, a reference solution for all 120 levels, the checker that re-proves the whole set, and a perpetual royalty-free license to ship these levels inside your own commercial game. Link below.