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Evil Sudoku

The hardest tier we offer — also called extreme, very hard or diabolical. Experts only.

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Evil Sudoku is the toughest level on Sudoku.tips. You will also see this difficulty called extreme, very hard or diabolical elsewhere — they all describe the same thing: minimal clues and the deepest logic.

What an evil puzzle demands

Everything from the expert tier and then some: long forcing chains, coloring, and patience under uncertainty (without ever guessing). Expect to spend serious time and to keep impeccable pencil marks.

Who evil Sudoku is for

Veteran solvers chasing the hardest fair puzzle a computer can guarantee. Every grid still has exactly one solution reachable by logic alone.

Frequently asked questions

Is evil the same as extreme or very hard Sudoku?
Yes. Evil, extreme, very hard and diabolical are different names for the hardest tier — minimal clues, advanced techniques required.
Do evil Sudoku puzzles require guessing?
No. They are still uniquely solvable by logic, but they need advanced chains and coloring rather than simple deductions.