Volume 1 of the Deadliest series was the hardest Killer Sudoku DJAPE had published at the time. Volume 2 raises the bar. The cages are more complex, the deduction paths are longer, and the moments where you think you are stuck last longer before the breakthrough comes.
At this level, every puzzle is a project. You will spend real time on each grid - not minutes, but potentially an hour or more. The Rule of 45 alone will not save you. You will need innies and outies applied in unexpected configurations, cage splitting across multiple intersecting regions, and hidden subsets that span cages.
This is book 2 of 5 in the Deadliest series, which sits above the 10-volume Revenge series in difficulty. If you have completed the Revenge series and want to test whether your skills have truly plateaued, the Deadliest series will answer that question quickly.
6 x 9 inch format. All solutions included. No guessing - every solution is reachable through pure deduction.
Created by DJAPE, whose Killer Sudoku books have established the definitive difficulty progression: Easy → Revenge (10 vols) → Deadliest (5 vols) → World's Hardest (3 vols). PhD in Computer Science, 250+ books, Washington Post weekly since 2006.