Board game
15×15 · freestyle by default · optional renju (Black bans)
Playfulo Gomoku — also called omok or five in a row — is played on a 15×15 board. Play against AI or a friend with no sign-up.
The default is freestyle (no forbidden moves). You can switch to casual renju, where Black may not play 3-3, 4-4, or overlines.
Choose easy, normal, or hard, or share an invite link with a friend.
Black plays first in the first game (after that, the winner moves first), then players alternate. The first to make five in a row — horizontal, vertical, or diagonal — wins.
Easy focuses on nearby attacks and blocks. Normal compares continuous threats and (in renju) common forbidden shapes. Hard searches a wider set of follow-up threats and defensive replies.
This is the center of a 15×15 board. Black has three stones in a row, plus one more stone just above the right end. Both ends are empty, so the next move can make an open four. The line below is what Playfulo's gomoku AI played when given this exact position 80 times at each difficulty, and what happens if White does not block.
Start
Both ends of the three-stone row are empty. Another black stone sits just above the right end, so leaving that end open lets Black connect. The picture is a close crop of the full board.
Line 1 / 4
Both moves stop an immediate four. The difference is whether White also separates the black stone above. Blocking only the left end leaves the right end touching that stone.
Hard 80/80
This stops the four and takes the point that would connect the stone above. One defensive move also slows the next attack.
Easy and Normal, about half
The open three itself is stopped, but the right end stays empty and can join the stone above. Easy chose this in 37 of 80 trials, Normal in 39 of 80.
Every difficulty blocked one end of this open three in all 80 trials. They split on which end. An immediate five-in-a-row is a separate rule.
11 Oct 2026: Playfulo's gomoku AI was called 80 times per difficulty on this position. Easy and Normal draw among similar scores, so a fresh sample can shift the split a little. The 85% immediate-five block is the rate written in the engine.
Freestyle has no forbidden moves — first to five (or more) wins. Casual renju forbids 3-3, 4-4, and overlines for Black only; White has no bans. Playfulo defaults to freestyle.
Yes. Create a room (pick freestyle or renju) and share the invite link. You do not need the same browser — the link is enough.
Yes. When the game ends, tap 'Replay game' in the result card to step through your gomoku (omok) game from the first stone. You can go back and forward, jump to the start or end, autoplay, or drag the move slider, and the winning five-in-a-row is shown on the last move. Replay works in both AI and friend games.
An open four, with both ends free, wins on the next move unless you block it now. Block that line first. A four that is already closed at one end can wait if you can create your own open four on the same turn. In renju, Black cannot play certain double-threes, double-fours, or overlines, so a blocking square that is forbidden means you look for another block or at White's open three.