Medium Hyper Sudoku
Medium Hyper Sudoku — around 31 givens. Hyper regions overlap parts of four standard boxes each, which means a digit forced into one half of a hyper region also propagates into two boxes you weren't looking at.
Medium puzzles start to need basic pencil-mark techniques: naked pairs (two cells in a unit that can only be two specific digits) and hidden singles across wider units. A typical solve runs 7–15 minutes.
Free downloadable Sudoku puzzles across four variants — Classic, Killer, Sudoku X, and Hyper — with answer keys on the back pages. No accounts, no colour ink.