In Oktaeder ("Octahedron") players take turns to stack one of their marbles into the playing area, building up an octahedron as the game progresses. The object is to form lines of four marbles of the player's color.

Oktaeder is similar to Kessler's game Giseh! but with an octahedral playing area instead of a pyramid. A transparent stand is provided with the game to hold the base of the octahedron during gameplay.