Evil sudoku is the toughest challenge on SudokuFun. These puzzles start with very few clues and require precise, multi-step logic to solve. If you enjoy advanced techniques and long solving sessions, Evil mode gives you the depth and difficulty you are looking for.
Launch a puzzle instantly and refresh for unlimited new games. Track candidates carefully, use notes to map possibilities, and lean on hints only when you are truly stuck. You can also mix in Hard or Expert puzzles to keep your practice balanced.