The idea is deceptively simple: Guide a marble down a path without hitting any obstacles or straying off the course. The game is viewed from an isometric perspective, which makes it harder to stay focused on the direction the ball is to follow. There are tight corridors to follow and enemies to avoid. There is a 2-player mode in which players must race to the finish; otherwise you're racing against the clock. The rights to the game were passed across a multitude of developers and publishers. In 1991 Electronic Arts had publishing rights, and produced a copy of the game for the Mega Drive in North America and Europe. While this version is complete, music porting and text drawing is somewhat sloppy, some of the graphics were recreated, colors were changed (most notably, the marble is now red), and the marble's motion restrictions were somewhat relaxed (allowing for jumps and drops not possible in other versions of the game). Atari Games' home console division Tengen produced their own Mega Drive copy for the Japanese market in 1993, which is different to the Electronic Arts version. This is similar to the situation regarding the Mega Drive port of Klax, in which Namco produced their own copy for Japan. This Japanese version, which appears to have been produced internally by Tengen of Japan, is much more faithful to the original game (but whether or not it is a direct port is unknown), and features trackball support through the Sega Mouse.