The Batlord

For me to call a genre extreme metal there has to be a general consensus that all of the bands in the genre must play extreme metal. Like, I wouldn't call thrash metal an extreme metal genre, since much of it was made up of bands like Anthrax, Annihilator, Metallica, etc, even though bands like Slayer and Kreator would qualify (I'd use "extreme thrash" to make the distinction.) But, for the most part, any death metal or black metal band is at least encouraged to play extreme metal. Many bands experiment with non-extreme metal forms of music, and some even dispense with extreme metal altogether at times, but as a status quo, those genres are explicitly concerned with being "extreme", rather than potentially less hardline concepts like "aggressive" or "hard" or "fast" or whatever.

Groove metal bands in general are more of the thrash metal mindset, where they're "badass", but aren't necessarily out to actually be extreme metal. So I'd consider the bands at the heavier end of the spectrum, like Pantera and Machine Head, to be flirting with extreme metal, even though their music might actually be more extreme than many actual extreme metal bands (Although I sometimes go back and forth with those two bands, depending which albums we're talking about.) A vague distinction perhaps, but it makes sense in my mind. Lamb of God though, at least their first two albums, I'd definitely consider extreme metal, since they were obviously going for extreme. I wouldn't be surprised if they played a few blast beats back in their early early days.

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