Arcade

Eight constraint-deduction puzzle games. Each shipped with verified correctness, difficulty calibration, legibility, and soft-lock fuzz testing. No accounts, no ads, no tracking — just open and play.

Lanternkeep

Memorize the room with the lantern lit — then deduce a safe path in the dark.

Nonogram

Picross / griddler. 10×10, line-solvable, one puzzle per page.

32 13 2
Slitherlink

Draw a single closed loop. Numbers count their edges.

34 23
Hashi

Hashiwokakero. Bridge the islands without crossing.

53· ··4 9·1
Sudoku

Classic 9×9, with technique-tier difficulty.

2102
Akari

Light Up. Bulbs on white cells; numbers constrain neighbors.

68 666
Shikaku

Partition the grid into rectangles. Each clue equals its area.

Star Battle

One star per row, column, and region. No two stars adjacent.

2→ 1↓
Yajilin

Numbered arrows count black cells along a sightline. Draw one closed loop through the rest.

4 5 3 4
Kurodoko

Clues count cells they see. Black some out, keep the whites connected, don't let two blacks touch.

234 123
Aquarium

Fill each tank to match the row and column water counts.

231 423 142 314 3 3 4 4
Hitori

Shade duplicates. Keep whites connected. No two blacks touch.