Hell · Easy
The gentlest hell
About 28 givens plus cage sums — still tougher than classic medium.
Hell Mode Killer Sudoku
Play Hell Mode Killer Sudoku online: cage sums, fewer givens, and a blank master tier with no starting digits — only cage clues.
Hell Mode
Killer rules apply: every cage must hit its sum with no repeated digits — and mistakes still count.
Hell · Medium
Rising heat
About 20 givens — steady killer deduction under pressure.
Hell · Hard
Serious pain
About 12 givens — advanced cage arithmetic and chains required.
Hell · Expert
Near the abyss
About 4 givens — expert killer techniques only.
Hell · Master
Maximum suffering
No givens — only cage sums. Deduce every digit from scratch.