It’s been a while since I last posted a Killer Sudoku variation. As far as I can remember, you folks liked the Butterfly layout of the puzzles, so here is an overlapping, 4-in-1 (Gattai-4), Killer Butterfly Sudoku puzzles.
You can also find these puzzles in my Killer Sudoku Compendium book.
Killer Butterfly Sudoku for Friday, January 29, 2010 – Difficulty: BRAIN.
Awesome! These are among my favorite variations (I’ve already done all the ones in the killer sukoku compendium). 🙂