A small rule-rewriting puzzle engine. Pick a game below; each page is static, works without a backend, and includes a scratch board editor for trying custom levels.
The clearest examples right now. Start here.
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A resource-management puzzle about oxygen, mining, construction, and getting back to your ship.
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A lockstep movement puzzle where multiple agents move together and force fields shape the route.
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The original UA4K puzzle set: small rewrite-rule levels about moving symbols into goals.
Playable experiments and demos. Some are intentionally small or strange.
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A tiny arithmetic toy built out of board rewrites.
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A minimal movement example for understanding the format.
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BALANCE:________10$__
A quick probability toy about wagering on which side has more dots.
1234
5678
9ABC
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Use wasd to slide.
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STAMINA:....----------------[-----]
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A compact turn-style combat toy.
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A Towers of Hanoi-flavored board rewrite demo.
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Game of Life (9 level(s))
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Pacman with buffered movement, scoring, lives, ghost modes, staged release, frightened ghosts, and four distinct personalities.
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The wolf, goat, and cabbage puzzle expressed as a UA4K game.
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A complete Snake implementation inside the puzzle engine.
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A small Sokoban-style box-pushing toy.
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A small symbol-manipulation puzzle with swap commands.
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A Tetris-shaped toy that stress-tests how far the engine can be pushed.
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A pursuit puzzle inspired by Theseus and the Minotaur.
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A tower-moving toy puzzle.
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A compact Turing-machine joke/demo implemented as a board game.