Yes. You play right in your browser with no download, and there is nothing to buy.

Can I play against my friends?

Yes. “Challenge a friend” opens a live duel; send your friend the code or the link. Each of you plays on your own device, and only the server knows both fleets, so nobody can cheat.

Do I need an account?

No. You play the AI without signing up, and you can join a duel as a guest. With a free PanicLines account you can open duels yourself, see your statistics and carry on on any device.

Yes. A game against the AI survives reloading the page. Without an account it stays in this browser; with one it is kept in your account. A live duel is kept on the server: if the connection drops, it carries on once you are back.

Sink the Fleet Online – Play the AI or a Friend

Play the classic fleet duel online for free

SeaStrike brings the classic fleet guessing game to your browser: you hide your fleet on a 10×10 grid and take turns with your opponent calling coordinates. “Miss”, “hit”, “sunk” – the first to sink every ship on the other side wins.

On PanicLines you play for free on phone, tablet and computer, with no download. Against the AI on three levels you start right away without signing up; friends can be challenged to a live duel with a code or link. A game takes about five to ten minutes.

Rules

The board has 10×10 squares: columns A to J, rows 1 to 10. Every square has a coordinate such as “B7”.
Your fleet has five ships: Freighter (5 squares), Ferry (4), Trawler (3), Sailboat (3) and Dinghy (2) – 17 squares in all.
Ships lie horizontally or vertically and must not touch, not even diagonally.
You take turns, one shot per turn – even after a hit. The answer is “miss”, “hit” or “sunk” with the type of ship.
Once a ship is sunk, the squares around it are marked as water automatically: by the touching rule no ship can be there.
Chance decides who starts. The first to hit all 17 ship squares of the opponent wins. You can give up at any time.

Modes and AI levels

Against the AI at three levels: Easy shoots at random and only sometimes follows up a hit, Medium searches in a checkerboard pattern and follows the line of a hit, Hard builds a probability map of every ship position still possible and shoots at the most likely square.
The AI never cheats: it only sees what you see – the results of its own shots.
Challenge a friend: open a live duel with your PanicLines account and share the six-character code or the link. Your friend can join as a guest, without an account.
In a duel every turn has 30 seconds. If time runs out, the server shoots at random for you; three missed turns in a row count as giving up.
After the duel one tap starts the rematch – and whoever lost last time goes first.

Controls

Placing: pick a ship from the tray and tap the board. Tap a placed ship to turn it, drag it to move it. On a computer R or a right-click turns it too. “Random” sets up a valid fleet in one tap.
Shooting: tap a square on the opponent's board to aim, tap it again to shoot – no shots by mistake. With “Confirm shot” off (settings) the first click shoots.
Keyboard: the arrow keys move the target, Enter or Space shoots.
Hits, misses and sunk ships have their own symbols (cross, circle, struck through), not just colours. Animations and sounds can be turned off.

Tips and strategy

Search in a checkerboard pattern: the smallest ship is two squares long. Shooting only every other square still finds every ship – with half the shots.
Find the line after a hit: try the four neighbouring squares. As soon as two hits lie side by side, follow the line in both directions.
Use the touching rule: squares diagonally next to a hit and all around a sunk ship are certainly empty. Shooting there wastes a turn.
Big gaps first: where a lot of open water hangs together, the large ships are most likely to fit.
Place unpredictably: don't set up your fleet the same way every time. Sometimes along the edge, sometimes in the middle – and don't always hide the dinghy in a corner.

Frequently asked questions

Is SeaStrike free?: Yes. You play right in your browser with no download, and there is nothing to buy.
Can I play against my friends?: Yes. “Challenge a friend” opens a live duel; send your friend the code or the link. Each of you plays on your own device, and only the server knows both fleets, so nobody can cheat.
Do I need an account?: No. You play the AI without signing up, and you can join a duel as a guest. With a free PanicLines account you can open duels yourself, see your statistics and carry on on any device.
Is my game saved?: Yes. A game against the AI survives reloading the page. Without an account it stays in this browser; with one it is kept in your account. A live duel is kept on the server: if the connection drops, it carries on once you are back.