Power chords take care of most metal. I think the end of 50% of all old Iron Maiden songs was a three chord power chord riff where it goes (fret postions on E,A&D strings respectively) 5,7,7 - 3,5,5 - 5,7,7. (Or 7,9,9 - 5,7,7 - 7,9,9) My old band in highschool started doing that at the end of every song just because, even .38 Special's "Hold on Loosely." No, no one actually watched up play this as our biggest basement crowd was 3 people. I was the singer then. I'm way off topic and babbling. Too much caffeine. ;)