Daily Brains · solo capture chess: every move takes, one piece must remain.
Mini Chess is the solo chess puzzle in Daily Brains (/daily). Each day sets three tiny wooden boards with a handful of pieces of a single colour. Every move must be a capture: any piece may take any other piece it attacks with ordinary chess movement. Keep capturing until exactly one piece is left. Run out of captures with two or more pieces on the board and you are stuck, so undo or restart. The boards get harder through the day and through the week, from a gentle 4×4 on Monday to a fiendish 6×6 on Sunday.
STORY & LORE
The week
Monday (Gentle) and Tuesday (Easy) use a 4×4 board with 4 to 7 pieces. Wednesday (Steady), Thursday (Tricky) and Friday (Tough) move up to 5×5. Saturday (Devious) and Sunday (Fiendish) are played on 6×6 with up to ten pieces. The weekday and its difficulty are shown beside the puzzle tabs.
How the boards are made
Every board is built backwards. The generator starts from the one piece that will survive and plays captures in reverse: the capturer steps back to a square it could have attacked from, and its victim reappears where it stood. So every board has a solution by construction. From Thursday to Sunday each reverse step is kept only if the position still has exactly one plan, so those boards have a single way through (independent captures may be made in either order). A solver in the test suite proves this for every banked board. Monday to Wednesday boards are tuned by how often random play gets through, so they start forgiving and tighten across the three puzzles.
The bank
The generator's output for puzzles #1 to #540 (through 10 March 2028) ships pre-computed in puzzles.js, so weekend boards appear instantly. Later days are generated live in the browser by the same code. The test re-derives sample days from the generator to prove the bank matches, and checks that no board repeats within a year.
HOW IT PLAYS
Moving
Tap a piece to lift it. Every piece it can take gets a red ring; tap one to capture it. Kings, queens, rooks, bishops and knights move as in chess. Pawns capture one square diagonally up the board and never promote. There are no checks and colours don't matter. On a keyboard, the arrow keys move a cursor and Enter picks up and captures; U or Backspace undoes, R restarts and N goes to the next puzzle.
Twists
King last (👑): the king can't be taken and must be the final piece. Two captures max (••): each piece may capture at most twice, and the dots under it count down. Frozen (❄): an icy piece never moves, but it can still be taken. The first twist arrives in Tuesday's last board; Sunday uses all three on every board.
Scoring
Each cleared board is worth 300 points, minus 25 for every capture you take back (an undo, or each move wiped by a restart), with a floor of 150. The day's maximum is 900. Give up (tap twice) and the game replays one solution for that board, which scores 0. Clearing at least one board keeps your streak. Clearing all three with no undos is a perfect day.
Sharing
The share card has one row per board with one square per capture: 🟩 for a capture you got right first time, 🟨 for one you had to take back and retry, and ⬛ with ✖ for a board you gave up on. Nothing in it gives away a position.
THE WEEK
| Day | Board | Pieces (I / II / III) | Twists | One solution |
|---|---|---|---|---|
| Monday · Gentle | 4×4 | 4 / 5 / 6 | none | no |
| Tuesday · Easy | 4×4 | 5 / 6 / 7 | III: two captures | no |
| Wednesday · Steady | 5×5 | 5 / 6 / 7 | II: two captures · III: king last | no |
| Thursday · Tricky | 5×5 | 5 / 6 / 7 | king last, two captures | yes |
| Friday · Tough | 5×5 | 6 / 7 / 8 | two captures, king last, 1 frozen | yes |
| Saturday · Devious | 6×6 | 7 / 8 / 9 | king last, two captures, up to 2 frozen | yes |
| Sunday · Fiendish | 6×6 | 8 / 9 / 10 | all three, up to 2 frozen | yes |
REWARDS
| Event | Reward |
|---|---|
| Clear at least one board | 15 Tickets |
| Clear all three with no undos (perfect) | +25 Tickets |
| Last One Standing (first clear) | ♞ Bronze · 10 Tickets |
| Clean Sweep (perfect day) | 🧹 Silver · 20 Tickets |
| Three in a Row (3-day streak) | 🔥 Bronze · 15 Tickets |
| Woodworker (7-day streak) | 🪵 Gold · 40 Tickets |
| Lone Monarch (30-day streak) | 👑 Legendary · 100 Tickets |
VERSION HISTORY
- Launch version in Daily Brains.
- Three boards a day from 4×4 (Monday) to 6×6 (Sunday), with king-last, two-capture and frozen-piece twists.
- Boards built by reverse play, with exactly one solution from Thursday to Sunday. 540 days pre-generated and verified by scripts/test-mini-chess.mjs.
- Undo, restart and give-up (replays a solution), streaks, statistics, and a spoiler-free share card.