Futoshiki

Expert Futoshiki uses 7×7 and 8×8 grids. With 49 to 64 cells and digits up to 7 or 8, the candidate space is large enough that you need systematic tracking. Pencil marks (notes mode) become essential.

At this level, combine all techniques: naked singles from row/column elimination, inequality forcing to bound cell values, chain propagation across connected constraints, and hidden singles when a digit has only one valid position in a row or column. The puzzles require patience and methodical work.