Eleven lines each way make 121 junctions; the centre junction is broken, so 120 tokens fill the board: 60 white (gold, worth 2) and 60 black (ink, worth 1) in a pattern of your choice. Light plays first. Your side is the five rows nearest you; the middle row belongs to nobody.
Opening: Light takes any full column of five on Light's side (those points become Light's passage); Dark then takes a column on Dark's side, but not the same column number. Taken tokens score for the taker and never return.
Choosing a kas: each player, Light first, brings one token into their passage from the two columns beside it. A token in the column next to the passage slides across; a token one column further jumps over its neighbour (the neighbour stays). The token that enters is that player's kas, the only piece that moves for the rest of the game. If the entry can capture a line (rules below), it must; otherwise it simply enters.
Play: on your turn slide your kas along a line over any number of empty junctions. It cannot pass or land on a token, the other kas or the broken centre, and every move must capture. After a sideways move it takes a line up and down through where it lands; after a move up or down it takes a line sideways.
A line is tokens of one colour running out from the kas in one or both directions. Empty junctions inside the line are skipped; a token of the other colour, the other kas, the board edge or the centre ends it. You may take any odd number of them (1, 3, 5, 7 or 9), nearest first. When there is more than one way to take, tap the last token you want in a direction; if that is an even count, add tokens from the other side; tap the kas to confirm an odd count you want to keep.
Suntuk: a player with no capturing move loses and hands every captured token to the opponent. When the last token is taken the higher score wins; equal scores draw.
Patterns: Chequer, Diamonds and Bands are mirror-symmetric in both axes; Random is a fresh 60/60 layout each game, symmetric through the centre. Online games use Chequer so both devices see the same board.
Rings mark the kas; dots show where it can land; the passage points carry a hollow mark. Undo takes back your last turn. Games save automatically: leave and pick up later.
Online: choose Online, create a game and share the code or link. Your friend opens it and plays from their own device.
Keyboard: arrow keys move between junctions, Enter or Space selects.