Even while the dawn of nu-metal presented a bunch of bands pushing heavy music in bold new directions, few Nineties acts felt as maniacally eclectic as System of a Down. The L.A. quartets 1998 self-titled debut smashed all barriers from the get-go, whether it was Suite-Pee colliding death-metal growls and disco beat subversion into frontman Serj Tankian eccentrically chirpy tenor, or Spiders creepy-crawling its way into our psyches as a bleak-but-beautiful ballad. Political, playful, and feverishly inspired, its one of heavy musics wildest first swings. And, yes, they knocked it out of the park.