All battleships (guns) and dominoes (sticks of butter) must be used exactly once.
No two battleships may touch each other, not even diagonally.
No battleship may be placed on a ~ symbol, which signifies blank/water.
Numbers outside the grid indicate how many battleship segments are in that row/column.
Here is an example puzzle and its solution. The example uses a double-4 set of dominoes and a reduced set of ships; the puzzle itself uses a double-8 set and a standard set of ships.
~
~
~
1
~
2
~
3
~
4
1
1
1
2
1
3
1
4
2
2
2
3
2
4
3
3
3
4
4
4
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
The puzzle below is interactive and supports undo/redo.
Click or Shift-click a cell to cycle through unknown, guns, and butter. You can also use the Space key for this.
Click the edge of a cell to place a domino between the two cells. You can also use Shift+arrow keys to do this.
You cannot place a domino in a place where it would be invalid (e.g. because a battleship is in the way).
You can click on the dominoes/ships below the puzzle to mark them as used.
You can undo with Ctrl+Z and redo with Ctrl+Y.
~
~
~
1
~
2
~
3
~
4
~
5
~
6
~
7
~
8
1
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
2
2
2
3
2
4
2
5
2
6
2
7
2
8
3
3
3
4
3
5
3
6
3
7
3
8
4
4
4
5
4
6
4
7
4
8
5
5
5
6
5
7
5
8
6
6
6
7
6
8
7
7
7
8
8
8
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
~
~
~
1
~
2
~
3
~
4
~
5
~
6
~
7
~
8
1
1
1
2
1
3
1
4
1
5
1
6
1
7
1
8
2
2
2
3
2
4
2
5
2
6
2
7
2
8
3
3
3
4
3
5
3
6
3
7
3
8
4
4
4
5
4
6
4
7
4
8
5
5
5
6
5
7
5
8
6
6
6
7
6
8
7
7
7
8
8
8
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
⚓
When the grid is complete, extract an answer by looking around the four 1x1 ships.