What are some of the most extreme vocals in metal

WOW! Amazing! Three pages and no mention of early Kataklysm? You guys have got to be new!

Check out Kataklysm _Temple of Knowledge_ or _The Mystical Gate of Reincarnation_

It's not that his voice is all that radical, it's how he uses it.

ack
 
For vocals that ruin an album Check out how excellent the instrumentation is on Spastic Ink's Ink Compatible... then listen in horror as the vocalist just goes through an unimaginably horrible routine.

coulda sworn that shit was an instrumental album when I heard it many years ago
 
Extreme vocals?I see.
Nergel(Behemoth)
Demilich guy.
Lyakthea guy.
Thergothon vocal(I don't understand a single word)

But all this are my fav bands,specially first 3 but you wanted extreme vocals & I like extreme vocals.
 
Meshuggah's vox are weird, because the vocalist mixes growl with some other kind of vocal. You don't hear that kind of singing often.

They're multiphonic from nothing onward. That is why I included them. He is singing 2 pitches at once, and is still comprehensible. I knew a chick who could scream multiphonically, but I doubt she could sing "what solace lies in the arms of fate" and have anyone understand her.

edit: you can hear 3 levels on the live in desth-is death on the nothing rerelease (or on youtube like me)