Freestyle
The best-known gomoku rule. Either color wins by connecting five or more in any direction — no forbidden moves, and an overline of six still counts.
Renju · official opening — the first five moves are scripted
Forbidden moves alone are not enough — many famous openings still favor Black. The RIF rule scripts the first five moves to rebalance the opening itself.
The opening ceremony
Black's first stone goes on the center point. White answers inside the 3×3 around it, and Black's third move lands inside the 5×5.
After move three White may take over Black — judging the opening shape and choosing the better color. For move five Black offers two squares and White picks one.
Why the extra steps
Even under renju, most classic openings favor Black. The swap option punishes a strong first placement, and the offered fifth move trims the opening once more.
It keeps more freedom than the Soosõrv rule's list of 26 approved openings while still reaching tournament-level balance.
How it plays here
Against the AI, the engine, playing White, decides both the swap and the fifth move. Online, White sees the choice buttons; on a shared screen the two players simply switch seats.
Common questions
What does 'White may take Black' mean?
After three moves White can claim the Black side of that opening shape — the colors swap and the player who was Black continues as White.
Why offer two fifth moves?
Instead of placing the single strongest point, Black presents two squares and White chooses — a second lever against a lopsided opening.
What is this rule formally called?
The RIF opening rule, used by the Renju International Federation in official competition.
See the other rules
Exact five
Exactly five in a row wins; a line of six or more does not. A simple compromise that weakens Black's overline attacks without forbidden moves.
Caro · cờ caro
The Vietnamese gomoku rule. Exactly five in a row wins — unless the opponent has sealed both ends of the line.
Renju
The official RIF rule. Forbidden moves — double-three, double-four and overline — apply to Black alone to erase the first-move advantage. White is unrestricted.
Gomoku · Swap2
The world-championship opening. One side places black-white-black, and the opponent either picks a color or adds two stones and hands the choice back. Wins need exactly five.