How to play
The rules of the daily board: a sudoku with mines under it, opened with rooks, bishops, knights and kings. The board can be 6×6, 8×8 or 10×10.
Start the guide Rather learn by doing? Hop in the train car and the knights will run you through a real board.
The goal
- There are mines under this sudoku. Defuse every one and the board is ours!
- One way: flag the mine, then run a rook or bishop through the flag.
- Or I raise my own flag and jump onto it!
- Or probe it: light the fuse on the cell and let it burn round.
- And if I just step on one?
- It blows up and takes one of our lives. A mine that blew up counts as done, though.
Every boom and every empty probe takes one of your lives: four on a 6×6 board, five on 8×8, six on 10×10. Lose them all, or have no piece left to play or move, and the board is lost. Probes don't count as moves.
You never have to guess. The board is built to be solved by logic from the cells that start open.
Controls
| To | Mouse | Touch |
|---|---|---|
| Place or move a piece | Drag it, or click it, then the cell | Drag it, or tap it, then the cell |
| Flag a cell | Right-click it | Double-tap it |
| Flag a knight | Right-click him | Long-press him |
| Pencil candidates | Hold the right button on it, slide to a digit, release; again for another, or to rub one out | Tap it, then tap digits on the wheel (again to rub one out); tap off the wheel when done |
| Probe a cell | Hold the left button on it | Tap it, then the fuse on the wheel |
| Discard | Drag it onto the newspaper | The same |
| Merge | Drag one hand piece onto another | The same |
| See a zone | Point at a piece or a number | Tap a piece, or hold a cell |
| Pause or give up | Click the glass of tea | Tap the glass of tea |
Playing a piece onto your own flag asks "Onto your flag?" first. Press Play it, or Stay to take the piece back.
On touch, a fast second tap in the middle of the wheel flags the cell instead of picking a digit.
In the train car the lamps over the window are your lives (a boom or an empty probe breaks one), the enamel plate counts the mines left, the chess box is the deck and the newspaper takes discards.
The numbers
- A sudoku with mines in it. So the mines are all the fours, obviously!
- No, the mines are their own layer. A 2 in a round token means two mines in the eight cells around it.
- The number on a block's frame counts the mines in that block. Cells that start open never hold one.
- That white king says 3. Three mines on the board!
- Around him. A white shield counts mines in the zone, a black diamond the closed cells hiding its digit.
- A rook or bishop looks along its lines, up to the first open cell or piece. A flag doesn't stop it.
Counts update after every action. A king's zone is the eight cells around him, a knight's the eight cells an L-jump away.
An empty dashed ring on a starting cell means it shows no count. It isn't a zero.
Placing a piece
- A piece on a closed cell says the cell holds its digit. Right digit: the cell opens, the piece stays.
- Wrong digit: the piece sits out for the rest of the board, and that digit goes grey on the cell.
- And on a mine I just bring the right digit, yes?
- A mine blows up whatever you carry. One life gone, and so is the piece.
- A rook or bishop merges with the cell he lands on: a 3 on a 3 makes 6. Kings and knights keep theirs.
Your hand holds five pieces and refills from the deck after every piece you play.
Moving on the board
- Land, then move again, and again. I could hop around all day!
- One stamina a move. You have three, the others two.
- A rook or bishop opens its whole path. A mine under your flag is defused, one without a flag blows up.
- And a flag with nothing under it?
- The piece stops there on a question mark and sits out. That's 10 points off.
- A rook can also glide along open cells for free. It opens nothing, it only lines up what he counts.
A board move follows chess rules onto a closed cell and doesn't check the digit. Placing from the hand costs no stamina.
A king's step or a knight's jump has no path, so your flag doesn't help: a mine there blows up.
A knight under his own flag defuses the mine he lands on and keeps jumping while he hits. On an empty cell he leaves a question mark, loses 10 points and sits out.
The probe
- I probed a cell and there was nothing in it.
- Then it's a question mark for good, 10 points off, and one of our lives. A mine would have paid 10.
- Not this time. The king took it for us!
- A king has one spare life a board. An empty probe in the 3×3 around him spends it instead of ours.
- And the second time?
- He leaves the board, and you get the question mark, lose the 10 and a life anyway.
Your hand
- My hand's full of digits that fit nowhere. There, I threw one away.
- Discards are free, and a new piece comes in. But the deck holds 18 pieces, and that's all.
- Or feed it to another piece in your hand. Their digits add up, round the circle.
- So a 6 fed to a 3 makes 9!
- On a 6×6 it makes 4. The 6 counts as 1, and the piece you fed is discarded.
The daily
One board a day, the same for everyone. A new one comes at midnight, UTC. It can be 6×6, 8×8 or 10×10: 5, 10 or 15 mines, and four, five or six lives.
You get one try. Give up in the pause and the day counts as lost.
Every move is saved in this browser. Close the tab and you come back to the same board. Starting a new Daily needs a connection to the board server. You can resume today's saved attempt offline; the guide and Endless work offline too.
A win adds 1 to your Daily streak. A loss keeps the count. A day without a finished Daily resets it to 0. The fire burns after a win, smolders after a loss, and is at risk until you finish today's board. At 0 it is out. Its 15 tiers grow with the count.
After a win or loss, vote once for tomorrow's 6×6, 8×8 or 10×10 board. You can't change your vote. The most votes wins; a tie or no votes means 6×6. Voting closes at midnight UTC, and the tally isn't shown. Steam sign-in is optional.
Connect Steam to sync finished Daily results and Endless boards between devices and get an unlisted profile link. Guests and each Steam account have separate histories and started boards on this device. Signing in claims unassigned guest play once; switching accounts restores that account's saves. An unfinished board stays on the device where you started it.
Endless is always 6×6. Its streak counts boards won in a row and resets to 0 on a loss. Your profile shows its boards, wins, losses, points and best streak.
The score is in whole points, just for fun. Opened digits earn points, more when the same move defuses mines. A probe on a mine earns 10, a question mark costs 10, and a blown-up piece costs 30 for a knight or bishop, 40 for a king and 50 for a rook. The score can go below zero.
The Daily result card shows this board's score, your Daily streak and your best score from played days. Your profile shows your best Daily streak. Copy shares a PNG with the tier fire, streak count, Daily number, board size, result grid and Steam name if connected. If image copying isn't available, it shares text such as "Daily #12 · 8×8 · streak 7", followed by your profile link if connected, or sudochessweeper.com/daily otherwise. The grid uses these marks:
Take the guide first New to the board? The knights give the same tour right before today's puzzle.
380a won board and its score
a lost board
a cell left closed
an opened cell
a defused mine
a boom