
A choose-your-own-adventure book of shape-packing logic puzzles set in a dreamlike world.




Here's an excerpt from CERT's itch.io description:
CERT is an explorable puzzle book. Discover a surreal, dreamlike world filled with classic deduction-based paper puzzles!
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Navigate an extraterrestrial land of sudoku variants to unlock further rules and abilities.
Pick up variant tools and fight self-contained bosses to explore the connected grids of planet Sudoku-45.
Explore the grid, gain new abilities and place the right digits in a huge sudoku-meets-metroidvania map.
Find the rules behind each suit and face card to solve the underlying logic puzzles.
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