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1.
heavy metal that sucks ass.
characteristics include:
-all songs sound the same
-no solos or breakdowns
-piece of shit vocals
-crap distortion that just makes noise
-most mainstream heavy metal

okay so butt metal means bands that just suck so much, and suck ass
butt metal includes the big names like:
megadeath, korn, metallica, disturbed, camshaft, burning graceland, nickelback, etc
by nabil, tyler, and sammy August 01, 2008