Sea Battle Probability Map: Best First Shots, Measured
The best first shots in sea battle are the centre cells: across 100,000 random fleets, the middle of our 10x8 board held a ship 23.6% to 23.9% of the time, and the corners only 7.8% to 8.0%. That map is the real one here, because on Playgridia nobody places ships. The server drops each fleet at random, so the numbers below describe every opponent you will meet.
Why the map is real: nobody places ships
Each side has four ships of length 5, 4, 3 and 2, which is 14 of the 80 cells. The server's random placer puts them down for both seats as the match starts, largest first, each one horizontal or vertical. There is no placement screen to play with and no button to press.
That kills two bits of old advice. You cannot hide a fleet, and "ships never touch" is false. Nothing in the engine checks spacing, so ships may sit side by side, end to end or diagonally, and they may sit on an edge or in a corner.
The open-sea heat map
We ran the engine's own placer 100,000 times and counted how often each cell held a ship. If every cell were equal, each would hold one 17.5% of the time. They are not equal.
| Where | Chance a ship is there |
|---|---|
| Even share (14 of 80 cells) | 17.5% |
| Centre cells | 23.6% to 23.9% |
| Corners | 7.8% to 8.0% |
| Edge cells, average | 15.7% |
| Inner cells, average | 18.5% |
Column by column, from the edge to the centre, the averages climb 12.6, 15.9, 18.3, 20.0, 20.8. The edge is not empty, though. 95.3% of fleets have at least one ship on the edge, and 72.3% have two ships touching.
Heat alone is a trap: hunt with a checkerboard
The obvious plan is to fire at the hottest cell each time. We tested it, and it loses. We modelled a single gun that, after a hit, shoots the neighbours until that ship sinks, over 20,000 fleets.
| Search order | Shots to sink everything | Shots to first hit |
|---|---|---|
| Random | 51.4 | 5.44 |
| Checkerboard | 48.0 | 5.18 |
| Checkerboard, ordered by the heat map | 47.0 | 4.19 |
| Heat order, no checkerboard | 55.3 | 6.30 |
Pure heat order is worse than random, because it wastes shots next to each other. Spread your shots on alternate cells, and inside that pattern start in the middle. That combination found the first hit in 4.19 shots on average and finished in 47.0.
This is a model, not our bot and not a human result. Real turns have wider guns and skills, one ship acts per turn, a hit gives no extra shot, and a hit does not tell you which ship it was. Treat the table as the shape of the advice, not a promise.
Which gun to shoot where
The carrier and destroyer fire one cell. The cruiser's Twin Salvo covers the tapped cell and the one to its right. The battleship's Broadside covers three in a row, centred on your tap. When you tap enemy water, the board picks the widest gun you still have, so you usually fire the best one without asking.
A three-wide line suits the middle of the board, and the middle is where ships are most likely. Open there. Once a ship is hit, work the neighbouring cells until its whole hull is shown.
Sink the battleship first
A sunk ship loses its gun and its skill. Sinking the battleship removes the three-wide Broadside, so every later tap covers less. Sinking the carrier removes its 3x3 Air Strike. A hit does not reveal which ship you struck, so you only learn it when the hull goes down and the whole ship is shown. There is no extra shot for a hit, so finish a wounded ship rather than wandering off.
Advice for each sea
Not every sea uses the open-sea map. We measured the other two the same way.
| Sea | What the map shows | What to do |
|---|---|---|
| Shoals | Cells beside the rocks are low. The open coast reaches 35.8%. | Rock cells are never valid targets, so skip them. Fire along the open coast first. |
| Strait | Deep channel averages 33.0%, shallows 7.2%. | The carrier and battleship must sit in the channel, so start there. |
| Storm | Same spread as the open sea. | A moving band blocks 2 columns each turn. Shoot elsewhere and come back. |
A note for paper and other apps
Everything above depends on a random placer. Where a person chooses, a person may avoid the centre, and the map would shift. We did not measure people, so do not carry these percentages to a paper game or another app unchanged.
Ready to try it? Read the rules guide first, then the strategy tips, or jump into a match and play sea battle online. Open in the middle, space your shots, sink the battleship early, and start on the Playgridia sea battle page.
Frequently Asked Questions
What is the best first shot in sea battle?
A centre cell. Over 100,000 random fleets, centre cells held a ship 23.6% to 23.9% of the time, while corners held one only 7.8% to 8.0%. Fleets here are placed at random by the server, so this applies to every opponent.
Can ships touch in sea battle?
Yes. The engine checks only that ships do not overlap, so they may sit side by side, end to end or diagonally. In our 100,000 random fleets, 72.3% had two ships touching.
Should I fire at the hottest cell every turn?
No. In a single-gun model over 20,000 fleets, pure heat order needed 55.3 shots to sink everything, worse than random at 51.4. A checkerboard pattern ordered by heat did best at 47.0.
Do ships ever sit on the edge?
Often. 95.3% of random fleets had at least one ship on the edge, and the average edge cell holds a ship 15.7% of the time. Corners are the thinnest spots, at about 8%.
Which ship should I sink first?
The battleship. It carries the three-wide Broadside gun, so sinking it makes every later shot cover less. Sinking the carrier also removes its 3x3 Air Strike.
Does a hit give me another shot?
No. The turn always passes, even after a hit or a sink. A hit also does not tell you which ship you struck; the whole hull is shown only when it sinks.