By break, I mean break into the mainstream. As we all know, a couple thrash bands have done it. Megadeath obviously did because they are softer, but I wonder what it is about Pantera and pre-black-album Metallica that caused them to gain popularity. Even though they are not metal, Slipknot managed to break into the mainstream whilst having harsh vocals and blastbeats. I wonder if any extreme metal bands have the qualities to make them quite popular. There are a few death metal bands that I think could attain the popularity that Pantera once enjoyed.