Guilty Gear X2

Guilty Gear XX is one of the best two-dimensional fighting games ever, in my opinion. The visuals are amazing; even perfect. The characters are interesting and varied, as well as humorous, and the music is probably the best collection of Rock you'll find in any video game. It's an easy game to play at first, but tremendously more fun once you know what you're doing. Plus, going back to that music, the makers were kind enough to provide a sound test in the options to listen to all the music, even secret and rarely-appearing songs. The story mode is interesting and fun, arcade mode is a fun diversion, and mission mode is a great challenge (emphasis on challenge). If you can find a copy, get it. If you can't, get one of the variants of it.