About Bimaru Fleet
Solitaire battleship is a deduction puzzle wearing a naval theme. A six-ship fleet sits in the grid, and edge numbers tell you how many ship squares each line holds. Revealed squares break the symmetry. Ships never touch, even at a corner, so every ship you find gives you a ring of water around it.
Every daily board is generated with exactly one solution and checked before it ships. If you get stuck, revisit the counts and the water ring around each ship before committing to a guess.
The fleet has six ships — lengths 4, 3, 2, 2, 1 and 1 — occupying 13 cells. Do not count a revealed ship twice when checking a row or column total.
Strategy tips
- Start with the zeros. A row or column marked 0 is entirely water, and that usually decides the ends of ships in neighbouring lines.
- A full line is just as generous: if a row of seven needs seven ship squares it is solved, and if the count matches the blanks left, so is that line.
- Every ship square you commit to surrounds itself with water diagonally. Marking those diagonals immediately is what turns one deduction into four.
- Place the four-square ship early. It only fits in a few places once the counts are read, and pinning it collapses most of the remaining ambiguity.
- When two arrangements of a small boat both look legal, count the column totals they would force. One of them almost always overshoots.
Controls
Tap or click a square to cycle it between ship, water and blank. Revealed squares are fixed and cannot be changed. Use Check to highlight any ship square you have marked over open water.
For another constraint grid, try Sum Cross, or the Nonogram, which also reads its clues off the edges.