Concentration

A tile-matching memory game for Windows 3.1: turn over two tiles, keep them if they match, start again if they don’t. Three board sizes, from a gentle 4×4 up to an 8×8 that holds sixty-four tiles and thirty-two pairs. It kept your turn count in a status bar along the bottom, and it could save a game in progress and restore it later, which felt worth building at the time.

The tiles are the part I’d forgotten. Thirty-two hand-drawn 48×48 bitmaps — a bell, a lit bomb, a snowflake, an open book, a crescent moon with a star, a paper airplane, a skull, a smiley and a frowny, a mailbox, and a run of hand gestures: thumbs up, thumbs down, an OK sign, a pointing finger for every direction. Someone drew all of those a pixel at a time.

This predates Combat Tanks by two years, which makes it the earliest surviving thing from Red Herring. The window code has the same fingerprints the later games do — the same way of measuring text before sizing a window, the same light gray background, the same habit of aligning every variable declaration into a column.

Its source code survived. Combat Tanks’ didn’t.

That difference turned out to be the whole story. Rebuilding Combat Tanks for the browser in 2026 meant disassembling the shipped binary and recovering the rules by inference, a week of work to learn things I’d written myself. Concentration took an afternoon, because CONCENT.C still exists and the rules are simply sitting in it — the grid sizes, the flip-and-reset logic, the exact wording of the status line. I didn’t have to deduce that matched pairs stay face up while the mismatched ones flip back on your next click. I just read it.

Play it in your browser — original art, original rules, ported from the original source.