Use it
Agile Battleships
Three rounds against the same seven ships, with the same thirty shots and the same five minutes. Nothing changes between them except how often you find out whether it is working. Most people score two or three times better by the third round without getting any better at Battleships.
Play a game
Three rounds — the whole thing takes about ten minutes
The board is interactive, so it does not print. Play it at michaeloreilly.me/battleships — or take the rules from michaeloreilly.me/battleships-about onto a sheet of squared paper, with someone else holding the answers, which is how the exercise is usually run in a room.
The game itself needs JavaScript, which appears to be switched off — so neither playing on your own nor joining a session is going to work from here. The rules are one tab across, and they work perfectly well on a sheet of squared paper with someone else holding the answers, which is how the exercise is usually run in a room anyway.