How to play

Both sides hide a fleet of five ships on a 10 × 10 sea: ships of length 5, 4, 3, 3 and 2, placed in straight lines, across or up and down, and never overlapping. Your fleet is placed for you; press Shuffle my fleet until you like the layout, then Start. Then take turns firing, you first. Tap a square on the enemy sea to fire. A dot means a miss, a cross means a hit, and when every square of a ship has been hit it is sunk and shown in dark red. After each of your shots the computer fires at your fleet. The first side to sink all five enemy ships wins.

The computer has three levels. Easy fires at random squares. Medium follows up a hit by trying the squares next to it and otherwise fires in a checkerboard pattern. Hard works out, for every square, how many ways the ships that are still afloat could fit there, and fires at the most likely one. The game is hidden-information, so there is no 2-player mode on a single screen.

Tips

A ship is never shorter than two squares, so you don’t need to fire at every square: firing every second square in a checkerboard pattern is guaranteed to touch every ship. When you get a hit, fire at the squares around it until you find the direction, then follow the line to the end and back. A ship that has been sunk takes its squares out of the search, so you can ignore the squares around it. Note which ships are still afloat, because the longest one left tells you how far apart your shots can be.