Alien Syndrome is a run-and-gun arcade game created by Sega and published in 1987. Tengen produced both licensed and unauthorized versions of three NES games (R.B.I. Baseball, Gauntlet, and Pac-Man). The cartridges for their illegal games are spherical and matte-black, similar to the original Atari cartridges, rather as the gray, semi-square form of licensed NES games.