Catdoku

Place exactly one cat in every row, every column and every colored region. On top of that, no two cats may ever touch, not even diagonally. Fill the board without breaking a rule and the level is solved.

No. Every one of the 4000 levels has exactly one solution and is verified to be solvable by pure step-by-step logic. If you are stuck, the hint paw points at the area where the next forced move hides.

The board freezes and shows you exactly which rule the cat broke, highlighting the conflicting row, column, color patch or touching neighbour. Each mistake costs one of the level's lives; lose them all and the level is over. Later chapters hand out fewer lives, so the endgame boards forgive less. If a level gets away from you, the reset button clears the board and hands your lives back.

There are 4000 levels across seven chapters. Sunny Windowsill grows from 5x5 to 10x10 with steadily deeper logic. Night Prowl revisits 7x7 through 10x10 where every board demands at least one deeper deduction. Rooftop Run only ships boards that require the hardest technique in the book, on 8x8 to 10x10 grids, and cuts you to five lives. Moonlit Alley moves to 9x9 and 10x10 boards that start above almost anything before them, with just three lives. Storm Drain keeps those sizes and three lives but leaves no easy boards at all, and every tenth level is a boss board. Belfry keeps the boss boards and three lives, and every board needs the counting trick several times over. Fish Market Raid is the longest chapter at a thousand levels, with the same tough boards and only two lives on every boss board. Every level also has its own written walkthrough if you want the full solution.