A battleships game to play against the computer

Sea Battle in Games by Zaweba is the battleships game you're after. You hide your fleet of five ships on a grid, then take turns with the computer firing at squares of each other's hidden waters until one navy is on the sea bed. It's free, it runs offline and there are no adverts.

The pencil-and-paper version needs two players and a lot of honesty. Against the computer you get a fair opponent every time, and the splashes and flames do the bookkeeping for you.

Setting up your fleet

Place your five ships on your grid. They can touch, but they can't overlap. Drag each ship onto the grid, or click to pick one up and click again to drop it. To turn a ship, press R, right-click, or use the Rotate button. If you'd rather not decide, Auto-place arranges them for you.

Sea Battle is on the Board games shelf of Games by Zaweba, and the title card explains the rules and controls before you begin.

How the shooting works

Once both fleets are hidden, take turns firing at a square of the enemy's waters. A splash is a miss and flames mark a hit. When every square of a ship has been hit, it sinks. Sink all five enemy ships before the computer sinks yours to win.

To fire, click a square on the enemy grid.

Hunting and finishing

Spread your early shots. At the start you know nothing, so firing in a scattered pattern covers the sea better than shooting in one corner. A chequerboard pattern works well, because a ship that runs across several squares is hard to slip between your shots.

Once you hit, finish the job. A hit tells you a ship is there. Fire at the squares next to it to find which way it runs, then follow the line until the ship sinks.

Remember ships can touch. Because ships are allowed to sit side by side, a cluster of hits might be two ships, not one. Keep firing around the edges until each is sunk.

Use what's left. As ships go down, think about which sizes are still afloat. A gap too small for any remaining ship can't hide one, so you can stop firing there.

Hiding your own ships well

Don't make it obvious. Ships lined up neatly along an edge or packed together can be easy to find once one is hit. Try mixing directions, some across and some down, and spreading them about.

Use touching ships with care. Placing ships side by side is allowed and can confuse the hunter, but once one is found, the other is often found soon after.

Auto-place is a good starting point when you're new. Then try your own layouts and see which hold out longest.

Records and pausing

Esc pauses the battle, F1 explains the rules, and F11 makes the grids fill the screen. Games by Zaweba keeps your plays, wins and best score on the game's tile, and those records stay on your own PC.

The Board games shelf has plenty more against the computer. If you enjoy the deduction in Sea Battle, the Puzzles shelf has Hidden Mines, a mine-flagging logic grid, and Colour Code, where little black and white pins guide you to a hidden row of coloured pegs.