For me personally, the experience was Back In Black by ACDC. I noticed how it sounded heavier than all of the songs I had heard from other bands on the radio that night.
My first taste of extreme metal was from a Steve T. video, where he determined the musical accuracy of cartoon guitar animations. It was during a South Park scene where they were playing a Dying Fetus song, Second Skin, that I though, “This is over the top and rediculous.” I had no idea that Dying Fetus would later become one of my favorite bands to listen to.
Yeah, I asked my friend this questison, and he said Battery. I also looked up “heaviest Metallica song” a while ago, and Battery was the answer I took.
I remember when I was little, I was at my great aunts house, and she had Guitar Hero. My brother and I would do Iron Man over and over. Much later, was listening to the song Iron Man, and I thought how ACDC sounded a lot heavier, and that my taste had changed.
Now I’m back to appreciating a diverse range of metal, including Doom metal songs like Iron Man.