This year, we started posting some extra difficult Sunday Stumpers, about once a month. These will be quite tough puzzles, but with a logical path to be found (and solution videos to help). This tenth Sunday Stumper is a challenging Killer Sudoku by Prasanna Seshadri.
or solve online (using our beta test of Penpa-Edit tools)
Theme: Y Go Extra?
Author/Opus: This is the 220th puzzle from our contributing puzzlemaster Prasanna Seshadri.
Rules: Standard Sudoku rules. Also, the sum of the digits in each cage must equal the value given in the upper-left corner of that cage. Digits cannot repeat inside a cage.
Difficulty: 5 stars
Time Standards (highlight to view): Grandmaster = 20:00, Master = 30:00, Expert = 1:00:00