Omok

Omok with Renju rules on a 15 by 15 board. Take turns on one device or play online with an invite code.

Omok

Omok is five in a row on a 15 by 15 board, for two people. You can share one device and take turns, or play online by creating a room or joining with an invitation code. There is no computer opponent. Black moves first, the opening is free (the first stone can go anywhere), and there is no clock and no undo.

Renju restrictions, for Black only

Black has to make exactly five in a row to win. An overline of six or more is not allowed, and neither is a move that creates two fours at once (four-four) or two open threes at once (three-three). White has no restrictions and wins with five or more, overlines included.

A few details matter in close games. A Black move that makes exactly five wins even if the same move also forms a three-three or four-four. A move that creates an overline is refused even if it makes five in another direction. Three-three follows the international Renju interpretation: only threes that can actually grow into an open four count. If one of the two apparent threes is blocked, or the point that would extend it is itself forbidden, the move is legal.

Forbidden points are not marked on the board. If Black tries one, a low buzz plays, the status panel names the reason (overline, four-four or three-three), no stone is placed, and it is still Black's turn.

How a game ends

The game ends the moment either player completes a line horizontally, vertically or on either diagonal. If all 225 intersections fill up with no winner, it is a draw. The last stone played is highlighted. No score or ranking is kept; it is simply a match between two people.

Using the forbidden points

For White, Black's restrictions are the strongest weapon on the board. If the point Black must block is a forbidden point for Black, Black cannot block it.

As Black, turn that around. Before you commit to a defense, check whether the blocking point would be a three-three or four-four for you; with no clock there is no reason to rush. And remember that your winning move is fine even if it is also a double.

Local and online

In local play the badge at the top shows whose move it is, and New game clears the board at any time. Black always starts, so swap seats to change who goes first.

Online rooms hold exactly two players, with no spectators. Colors follow the seat order in the room, and the badge shows your color and whose turn it is; the board is locked during your opponent's turn. After a game, both players have to press Request rematch to start the next one, and colors stay the same. If your connection drops, reconnect from the OWOGG connection panel and, as long as the room is still open, the game picks up where it left off.

Click or tap an empty intersection to place a stone. The top buttons switch Korean or English and toggle sound.