Lines of Action
Move by the count of the line and link all your checkers into one group.
How to play Lines of Action
You are Black and move first. Click one of your checkers to see its legal squares, then click a highlighted square to move. A piece always moves in a straight line (horizontally, vertically, or diagonally) exactly as many squares as there are pieces of either colour standing on that whole line. You may leap over your own pieces but never over an enemy, and you land on an empty square or capture an enemy there. Your goal is to be first to gather all of your pieces into a single connected group (touching sideways, up-down, or diagonally). Tap the 2P button to play a friend instead of the computer.
The capture that helps your opponent
Here is the strangest fact in Lines of Action, and the fastest way to start playing it well: taking an enemy piece often does the enemy a favour. The goal is not to wipe the other side out. You win the instant all of your pieces form one connected group, touching in any direction, diagonals included. Fewer pieces are easier to gather, so every checker you capture leaves your opponent with a smaller, quicker job. Ten pieces need ten links; seven need seven. Strong players capture for a reason (to break the enemy group apart, to fix their own shape, to remove a piece that ruined a key line) and never just because a piece was there for the taking.
Count the line, then move
Movement is the other twist. A piece moves in a straight line, horizontally, vertically, or diagonally, exactly as many squares as there are pieces standing anywhere on that whole line, both colours counted. Sit a checker on a diagonal holding two other pieces and it must slide exactly three squares along that diagonal, one way or the other. You may leap over your own pieces but never over an enemy, and you land on an empty square or capture the enemy standing there.
This means every move changes the board twice: once where the piece lands, and once on every line it left or joined. Add a piece to a line and everything on it moves further; remove one and everything moves shorter. A worked defence: your opponent's checker eyes a landing square three away along a row that currently holds three pieces. Step one of your checkers onto that row and the count becomes four, so the move they wanted is suddenly the wrong length. Nothing was captured, nothing was threatened, and their plan is gone. Checking those counts before you commit is the core discipline of the game.
Ideas that win games
- Keep your pieces central and loosely clustered. Corner pieces are the hardest to connect and the slowest to rescue, and one stranded checker can cost a won game.
- Play toward one mass, not two. Two tidy clumps that cannot reach each other lose to one ragged clump that is connected.
- Watch the enemy's shape as closely as yours. The sharpest move is often the capture that snaps their nearly-finished group in half.
- Before every move, re-count the lines it changes. A quiet step can hand the opponent a move they did not have last turn.
From the start, the shape is against you
The game opens with your twelve checkers spread along two opposite edges of the board and the enemy's along the other two, which is close to the worst connection shape possible. The whole early game is about swinging the wings toward the middle. Central squares sit on more busy lines, so pieces there have more moves and more ways to link up. Edge pieces have fewer, and a checker that lingers on the rim while the rest of your army gathers becomes the game's whole story: you spend three moves fetching it while your opponent finishes. Move your worst-placed piece early, not last.
There is a rhythm to a good game: a few quiet gathering moves, then a sharp one when a line count happens to fall your way. Because distances change every single turn, tactics appear out of nowhere, and the player who re-counts the lines each move simply sees more of them. Play slower than feels natural. Most lost games die to a move that was legal last turn and forgotten this turn.
A designer's game
Lines of Action was invented by Claude Soucie, a friend of the American game designer Sid Sackson, and it reached the wider world through Sackson's classic 1969 collection A Gamut of Games. It has been a favourite with abstract-strategy players ever since, with championship play at the Mind Sports Olympiad, and it became a standard test game for artificial intelligence research at the Computer Olympiad, where programs now play it frighteningly well. The connection goal is what keeps people coming back: it produces sudden, satisfying finishes, and a quiet-looking board can be one move from a complete chain. You play Black and move first here. The computer comes in Easy, Medium and Hard, and the 2P button hands the White pieces to a friend instead.
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Lines of Action: frequently asked questions
How far does a piece move in Lines of Action?
Count every piece (yours and the opponent's) on the straight line the piece would travel along. It moves exactly that many squares in either direction along that line.
When do you win Lines of Action?
You win the instant all of your remaining pieces form one connected group, where connected means touching orthogonally or diagonally. Captures can help by removing an enemy piece and pulling yours together.
Can I play against another person?
Yes. Tap the 2P button for local pass-and-play on the same device, and tap it again to switch back to the computer opponent with Easy, Medium, and Hard difficulty.
How far does a piece move?
Exactly as many squares as there are pieces of either colour standing on the whole line it's travelling along: horizontal, vertical, or diagonal. Count every piece on that line, yours and the enemy's, to get the distance.
How do you win?
Gather all of your own pieces into one connected group, where pieces count as connected if they touch sideways, up and down, or diagonally. The moment your last piece joins the group, you've won.
Can I jump over other pieces?
You may leap over your own pieces on the way, but you can never jump over an enemy piece. You land on an empty square, or capture an enemy piece that's sitting on your landing square.
Do captures help me or hurt me?
Both. A capture shortens every line through that square and changes what both sides can do. But remember the goal: with fewer pieces, your opponent has less to connect, so pointless captures actively help them. Capture to break their group or to fix your own shape, not just because you can.
Why are corner pieces risky?
A piece in a corner or on an edge is the hardest to knit into your group and the slowest to bring back toward the centre. Leaving one stranded there is a common way to lose a game you were otherwise winning.
What should my first few moves do?
Swing your wing pieces toward the centre and start forming one loose mass. Central squares sit on more lines, which means more moves and more ways to link up later. Leaving a checker behind on the rim is the classic way to lose slowly.
Is Lines of Action free to play?
Yes. Lines of Action is completely free on Inkplay, with no download, no sign-up, and no in-game purchases. Open the page and play instantly on desktop or mobile.
Can I play Lines of Action unblocked?
Yes. Lines of Action runs entirely in your browser with no download, install, or plugins, so it loads instantly and keeps working even on school or work networks where bigger game sites get blocked.
More games to play
In the mood for more? Try Chess, Tic Tac Toe, Connect Four, Reversi, or browse all board games and the full games list on Inkplay. Lines of Action also appears in 2 Player Games.