Battleships
Place the fleet using logic alone
Battleships (also called Bimaru or Solitaire Battleships) is a ship-placement logic puzzle inspired by the classic board game, but played solo using pure deduction. Given a grid with row and column counts indicating how many ship segments appear in each line, plus optional hint cells, you must place an entire fleet without any ships touching each other — not even diagonally. The combination of counting constraints and spatial exclusion rules creates a rich logical deduction challenge.
History & Origins
The two-player guessing game Battleship dates back to World War I, when it was played with pencil and paper by soldiers. Milton Bradley released the board game version in 1967. The solitaire logic puzzle variant — where you place ships using row/column clues — was invented by puzzle designer Moshe Rubin and popularized in the 1980s and 1990s through puzzle magazines. Known as "Bimaru" in some countries, it became a staple of logic puzzle competitions worldwide.
How to Play Battleships
The Fleet
You must place a standard fleet: one 4-cell battleship, two 3-cell cruisers, three 2-cell destroyers, and four 1-cell submarines.
Row & Column Counts
Numbers along the edges tell you how many cells in that row or column contain ship segments.
No Touching
Ships cannot touch each other, even diagonally. Every ship must be surrounded by water on all sides.
Ship Shape
Ships are always straight (horizontal or vertical), never bent. A 3-cell ship occupies three consecutive cells in a line.
Hint Cells
Some cells are pre-revealed showing water, ship middles, ship ends, or submarines. Use these as anchor points for deduction.
Complete Coverage
Place every ship in the fleet. The row and column counts must match exactly when all ships are placed.
Strategy & Solving Tips
Expert Battleships solving combines counting logic with spatial constraint reasoning. These techniques help you place the fleet efficiently.
- Start with rows or columns that have a count of 0 — fill those entirely with water
- If a row or column count equals its length, every cell in that line contains a ship segment
- Place the largest ship first (4-cell battleship) — it has the fewest valid positions
- Ship ends and middles in hints constrain orientation and neighbors immediately
- After placing a ship, mark all diagonally adjacent cells as water (the no-touching rule)
- Track remaining ships: if you've placed all submarines, any remaining isolated cells must be parts of larger ships
Battleships FAQ
Is this the same as the two-player Battleship game?
It's inspired by it but played solo. Instead of guessing where an opponent hid ships, you use logical clues (row/column counts and hints) to deduce the exact placement of every ship.
Do ships have to be a certain distance apart?
Ships must not touch each other in any direction — horizontally, vertically, or diagonally. This means there's always at least one cell of water between any two ships.
Can ships be placed diagonally?
No. Ships are always horizontal or vertical, occupying consecutive cells in a straight line.
What are the submarine pieces?
Submarines are 1-cell ships. They appear as a single occupied cell completely surrounded by water. There are four of them in a standard fleet.
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Ready to Play Battleships?
Command the fleet in Battleships — the solo logic puzzle where row and column clues guide you to the one correct placement. Strategy, counting, and spatial reasoning unite in this naval challenge.