Gipf is the first game of the series, and also the "hub" that ties all
the games together through the use of additional pieces.
Boardspace implements all three official variants - the basic game
without gipf pieces, the standard game with gipf pieces, and the
Gipf is superficially a simple variation of 4-in-a-row, where the rows
are created by sliding pieces toward the center. But superficial is the
key word, because it's a very deep brain burner of a game.
Read the official
rules on the project Gipf web site.
Strong players haven't reported yet, but the bot is good enough to be a
challenge to beginners.