Play Hell Mode Killer Sudoku online. Each cage shows a sum, digits cannot repeat inside it, and classic row, column, and box rules still apply. Classic Sudoku without cages is a different page.
Hell Mode is Sudoku Hot’s full Killer Sudoku experience. Every puzzle keeps classic row, column, and box rules, then adds dotted cages with sum clues. That combination rewards careful arithmetic, candidate control, and patience.
Each cage shows a small total in its corner. Digits inside that cage must add up to the total and cannot repeat, even when the cage crosses several boxes. After every cage deduction, classic Sudoku scanning usually reveals new singles.
Start with cages that have very small or very large sums. Those totals have fewer legal digit combinations, so they constrain the grid faster than medium-sized cages.
Hell Easy still includes around 28 givens so you can learn cage logic without drowning in candidates. Medium and Hard remove more clues and force longer deduction chains. Expert leaves only a handful of givens, and Master starts blank: only cages guide the solve.
A two-cell cage of 3 can only be 1 and 2. A two-cell cage of 17 can only be 8 and 9. Write those pairs, then scan the rows and boxes they touch. Hell Easy still shows about 28 givens so you can check the cage against the grid. Master starts blank: only the cage totals remain.
Yes. Hell Mode is Sudoku Hot’s Killer Sudoku board: classic Sudoku rules plus cage sums across five difficulty tiers.
Yes. Hell Mode uses the same mistake limits as classic play. A wrong digit can end the run, so treat cage totals as hard constraints.