During the heyday of the arcade game in the early 1980s, video game companies cranked out clones of popular titles, in the hopes that lightning might strike twice. 1979's Asteroids was a smash hit, one of the greatest video games ever, and thus it spawned all manner of copycats and sequels. Space Duel may not be a sequel in name, but improves upon the hallowed Asteroids formula in unique and entertaining ways, enabling it to stand on its own as a Co-Op Classic.