MattorKreul

A forced-checkmate puzzle collection set like a literary journal: warm paper, hairline rules, giant serif numerals and an engraved board. Every position has one forced checkmate and one key move that starts it.
Lead story: the Ladder
84 folios on three rungs: 30 mates in one, 30 in two and 24 in three. Some have black to move. Each folio opens after the one before it. Solve with no slips and no hints for three stars, with one for two, or with more for one. A large numeral beside the board tells you how many moves the finish takes.
Desk deadline
Three minutes, three slips. Puzzles run from easy to hard, a skip is allowed, and the deadline record and a journal of runs are kept.
The archive column
A quiz on the history of the game: 10 questions per round from 25 real facts, from chaturanga and shatranj to the Evergreen Game of 1852 and the first computer to beat a reigning champion in 1997. Each answer comes with a note in the margin.
Plates
Twelve bookplates for milestones, such as First Proof, Ten Folios, Clean Copy and Against the Deadline.
Index
Folios solved, stars, the share of clean solves, the deadline record, average time, hints taken, progress for each rung and a journal of the last 20 entries.
Notices
• Full legal move rules, including castling, en passant and promotion, with notation shown as you play.
• Hint marks the key in red, and Restart sets the folio back.
• A contents drawer lists each section with Roman numerals and page numbers.
• The animated background is paper grain with a slow shimmer and drifting line drawings of pieces. Switch it off in the Colophon, next to haptics and a progress reset.
• The game plays offline with no account needed.