Solo with 3x3 jigsaw + killer at unreasonable difficulty is the most fun I've ever had solving sudokus, requiring some really novel logic. In comparison, the no

Solo with 3x3 jigsaw + killer at unreasonable difficulty is the most fun I've ever had solving sudokus, requiring some really novel logic. In comparison, the normal 3x3 at unreasonable difficulty is really tedious, often devolving into a series of trial and error decisions.