To be honest, it's gotta be Pantera's The Great Southern Trendkill. Haha, extreme enough? Probably not. Today I consider Pantera on the lighter side of metal (like if you cut metal into two halves, with flower metal being one extreme and slam death the other). I don't even consider Suicide Note Part 2 heavy anymore. But there are little segments of that album that are extreme. I'd consider Suicide Not Part 2 a grindcore song....
Oh Shit, wait a minute...! That's not true at all. I always forget about the fact that I got into metal when my entire life had just become entirely different in every way, and all of the music that I used to love instantly seemed completely obsolete and unrelatable. So I started listening to the most extreme metal I could find because I needed something that was different from everything I had heard before. It was no Mexican Disgorge though, I was mainly listening to Dimmu Borgir, Meshuggah, Entombed, Voivod, Darkthrone, and Pig Destroyer. I can't beleive I always forget about that period of my life. I guess it's because it was so seperate from everything else, and I returned back to normal after it. And then I had to climb the metal ladder with Metallica and Pantera before getting back to the extreme metal that had already been my favorite music in the world at one point.
Getting BACK into extreme metal the first extreme metal album I liked was Cryptopsy's Once Was Not (if we're not counting TGSTK). But I only would listen to a few tracks at a time. Black metal was the thing that took me the longest to get back into. Even Dimmu. I actually thought I hated black metal for a while but now it's my favorite style of music.
