A game where the objective is to build five black stones in a vertical, horizontal or diagonal line, while avoiding building five white stones. Different rules apply for building on the second line in the corner.

It is worth noting that building five stones on the second line at the corner is not a viable option. Even if an extra black stone is only one line away, it is still possible for the black player to win using the small.
In the event that black cannot achieve a complete victory, the next best move is to make a small reduction in sente. It is also possible to play at position "a", although this comes with the added risk of giving white an extra ko threat.
Overall, this software provides a helpful tool for players hoping to improve their five-stone strategy.
Version 10: non