Hactar can play both go and capture go. Capture go is easier game for the computer, so Hactar can play it against you without a server. Hactar plays go using a server, this way Hactar has decent strength in go (Note: Hactar Lite plays at beginner level.) You can find more information from <a href="http://gowrite.net/hactar/client.php?lang=en">Hactar home pages</a>.
In following problems you need to identify last remaining place, where points could be gained, or reduced. The gained points are marked in the correct answer. The lost reduction opportunities are marked in wrong variations.