GomokuZero

GomokuZero is a Gomoku game built around an engine that explains its moves. After playing, it describes the shape your move created, what its reply took away, which alternatives it considered and why it rejected them. It also explains terms such as “open three” and “four” as they come up. You can ask it to suggest a move, explain why a move does not work, or say what decided its choice.

Play against the engine

The engine is a neural network trained by self-play, with four strengths ranging from a gentle introduction to a challenging opponent. You can play using freestyle, standard or renju rules; renju includes forbidden moves for black.

Other game modes

Play two-player games on one screen, with an optional clock. Online, you can play ranked games against someone near your rating or friendly games with a Steam friend. Ratings appear on the Steam leaderboard.

Learn and review

Ten lessons cover the rules, shapes, double threats, defending in the right order and renju’s forbidden moves. The game also includes 1,680 puzzles across five difficulty levels. Each puzzle was generated by exact search and checked by the test suite, so it has a solution that is proven to work rather than a “best guess” answer.

You can review any game you have played by stepping through it alongside the network’s assessment of each position. Stop at any move to ask what the engine would have done instead.

Offline play

The course, puzzles, engine and two-player games work without an account, connection or sign-in. The engine runs on your machine, and your moves are not uploaded. Games are saved as plain text files that you can read, keep or delete; only ranked play requires an internet connection, and the game makes that clear.

Languages

The teaching text, as well as the menus, is available in English, Simplified Chinese, Spanish, Japanese, Korean, German, French and Italian.