The "Classic Asteroids" game is actually a separate executable, but it cannot be run directly, only from the main game.
In early 2000, Activision and General Mills partnered to distribute CD-ROMs containing Asteroids
and other games with boxes of Cinnamon Toast Crunch
was the headliner of the disc.) The version of Asteroids
contained on the CD-ROM only allowed for two hours of play, but players could unlock the full version by paying over the Internet.