Abalone
Play Abalone, plus every pushing configuration enumerated: exactly three ratios can push, and a line of three cannot be pushed by anything.
Click one, two or three of your own marbles in a line to select them, then click a highlighted destination. You may move along the line or sideways, and you may shove the other side only along the line and only when you outnumber them. Push 6 of their marbles off the edge to win. Everything runs in your browser; nothing is uploaded.
There are exactly three pushes
You can never move more than three marbles, and the marbles in front of you are however many happen to be there, so the whole sumito rule collapses to a very short list. Enumerating every configuration — one to three pushers, none to three defenders, and whatever lies beyond them — gives exactly 2v1, 3v1, 3v2 and nothing else.
| Pushers | Defenders | Beyond them | Result |
|---|---|---|---|
| 1 | 0 | empty | slide |
| 2 | 0 | empty | slide |
| 2 | 1 | empty | push |
| 2 | 1 | the edge | push, off the board |
| 3 | 0 | empty | slide |
| 3 | 1 | empty | push |
| 3 | 1 | the edge | push, off the board |
| 3 | 2 | empty | push |
| 3 | 2 | the edge | push, off the board |
Those are all of them. Of 36 configurations, 6 are pushes, 3 are plain slides and the other 27 do nothing at all — 25% legal.
What the enumeration rules out
Every push has strictly more pushers than defenders. Equal numbers never move anything — not one against one, not two against two, not three against three. A single marble can never push at all, whatever is in front of it.
Which gives the game its central defensive shape: a line of three cannot be pushed by anything. Since nobody may move four marbles, there is no majority to be had against three, so three abreast is immovable by force and has to be gone round.
The other half of the rule is what sits beyond the marbles being shoved. It must be empty space or the edge of the board — one of your opponent's own marbles behind them blocks the push entirely, so a pair backed up by a friend is safe even from three. And only a push aimed at the rim ejects anything; every other push simply moves marbles about.
The opening position offers 44 legal moves and not one of them is a push — the two armies are not yet touching, which is why the first few turns are about walking into contact rather than fighting.
How to use
- Click one, two or three of your own marbles in a line to select them.
- Click a highlighted square to move along the line or sideways.
- You may only push along the line, and only when you outnumber the marbles in front.
- Whatever lies beyond those marbles must be empty space or the edge.
- Push six of the other side off the board to win.
Frequently asked questions
Which pushes are legal in Abalone?
Exactly three: two against one, three against one, and three against two. Enumerating every configuration — one to three pushers, none to three defenders, and whatever lies beyond — gives 36 cases, of which 6 are pushes, 3 are plain slides and 27 do nothing at all.
Can three marbles push three?
No. The majority has to be strict, and since nobody may move more than three marbles there is no majority to be had against three. That is why a line of three abreast cannot be pushed by anything and has to be gone round rather than through.
What stops a push besides numbers?
What sits beyond the marbles being shoved. It has to be empty space or the edge of the board — one of the defender’s own marbles behind them blocks the push entirely, so a pair backed up by a friend is safe even from three.
When does a marble actually go off the board?
Only when the push is aimed at the rim. Every other push simply shifts marbles along, so most pushing is about position rather than scoring. Six marbles pushed off loses the game.
Can a single marble push?
Never, whatever is in front of it — one against one is not a majority. A lone marble can only step into an empty square.
Does this send anything anywhere?
No. The game and the enumeration both run entirely in your browser and nothing is uploaded.
🔒 This tool runs entirely in your browser. Nothing you enter is uploaded, logged, or stored.