Logic
A growing shelf of logic puzzles you can play in the browser — Queens, Binary, Couples, Train Tracks, Galaxies, Yin Yang and the Polybius Box cipher. One rule each, hours of solving.
Binary Puzzles
Fill the grid with 0s and 1s — balanced rows, no three in a row, every line unique.
Couples
Place two markers per region so no matching pair ever touches.
Galaxies
Divide the grid into rotationally symmetric regions, one around each centre dot.
Polybius Box
Decode coordinate pairs into letters with the cipher grid — or deduce the key yourself.
Queens
Place one queen in every row, column and coloured region — none touching.
Train Tracks
Lay one continuous railway from the edge entry to the exit, matching every clue count.
Yin Yang
Fill every cell black or white so each colour forms one connected group — and no 2×2 is one colour.