Raster: Sudoku Variants

Sudoku with an honest difficulty scale. Each of the ten stages stands for one solving technique: the hardest one the puzzle needs. Nothing ever requires guessing. • 10 stages, from the last empty cell to X-Wing, Swordfish and forcing chains • Hints that name the next technique and point to the cells, not the digit • 15 rule sets: Classic, Killer, Thermo, Slow Thermo, Arrow, Jigsaw, X-Sudoku, Hyper/Windoku, Even/Odd, Sandwich, Kropki, XV, Renban, German Whispers and Between Line • Classic and Jigsaw also on a 6×6 grid • Fog of War: the grid only clears around correctly placed digits • A daily puzzle with a fixed weekly rhythm: gentle on Monday, hardest on Saturday • A handbook to look up every technique you have met and every variant rule • Nearly 5,000 puzzles, each with a unique solution and rated by the solver • Notes and auto-notes, undo, three error-display modes, optional timer, stars, best times and statistics • Works offline, no account needed WHY STAGES INSTEAD OF EASY, MEDIUM, HARD “Hard” means something different in every app. Raster rates every puzzle the way the sudoku community does: by the hardest human technique it requires. Stage 7 is not more of the same; it is where you need triples. When you reach a new stage, a short card shows the new technique with a worked example, so the ladder doubles as a course. VARIANTS WITH THEIR OWN LADDER Every variant is calibrated on the same 1–10 scale, so a stage 5 Killer feels as hard as a stage 5 Classic. The first time you meet a rule, a card explains it with a small solved example. Raster is free to play. After a solved puzzle a short ad is shown; a one-time in-app purchase removes it for good.