Terms of use

Available games and modes

Play Gomoku, Reversi, Firecracker and Sudoku. Gomoku and Reversi support computer, same-device and guest online matches. Firecracker is a solo number-path stage challenge; Sudoku offers board sizes and difficulty levels. These two newer games currently have Korean controls. Each game page explains its rules and controls.

The computer is a practice opponent, not a guaranteed perfect player. Online games use guest sessions and server-assigned colors, without accounts, nicknames, free chat or shared rankings.

The displayed game rules apply

Gomoku uses 15×15 Renju restrictions: Black cannot play double-threes, double-fours or overlines, needs exactly five to win, and forbidden clicks are rejected. White needs five or more. There is no tournament opening procedure. Reversi captures in eight directions on an 8×8 board, passes automatically when needed and ends when neither player can move. Read the guides for examples and exceptions.

Results are for playing under these rules. They are not official tournament records or certification of ability or qualifications.

Online waiting, cancellation and invite links

When the service is configured, find a random player in the same game or create/join a friend room. Matching may fail if no opponent is present. Queue waiting ends after two minutes; invite waiting after ten. You can cancel while waiting. Anyone with an invite can attempt to join, so share it with your intended opponent.

There is no online undo. Leaving an active game, switching modes or finding another opponent requires resignation confirmation. Read the server result, which can reflect board rules, time expiry, resignation or disconnection.

Online clocks and reconnection

Random and friend games use 30 seconds per move and last at most two hours, separately from offline time settings. A move is accepted when the server receives and validates it; a local click or device clock is not authoritative.

Disconnection allows a 60-second return grace, but the move clock continues and can expire earlier. The first applicable ending is used. Return uses the same tab’s stored secret; blocked or deleted storage may prevent recovery after a reload.

Saved information and shared devices

Offline progress, favorites and settings remain in the browser without server backup or automatic device synchronization. Online moves and state go to the server, and the per-game secret is stored in sessionStorage. Online state uses the cleanup limits in the privacy notice.

On shared devices, clear site data when appropriate. This can erase settings and progress stored in that browser.

Reporting issues and respecting content

Report incorrect rulings or controls using the email on the contact page. Include the game, mode, device, browser, turn and steps to reproduce the issue. Hide personal information in screenshots.

A game or image freely viewable elsewhere is not automatically free to copy or redistribute here. Check relevant rights and terms before using other material.

A shared lounge

Posts and comments appear after moderator review.

Respect others. No personal information, advertising or spam. Nicknames are not verified or exclusive. Official posts have a moderator label.

A post-management key stays in this browser. Clearing site data or switching devices removes your ability to delete your posts; contact us if needed.