Oh lol cmon where's the sense of humour?? But actually the more I think about it, the more it seems feasible... For some bands anyways. I'd have a better example, but right off the top of my head, a lot of vocals from CoF are rhytmic enough to qualify for rap lol.
Since growling vocals don't have any tone, its bacsially true. However, when used along with a lead guitar or keyboards, the vocals seem to take the same melody.
Example: anything Ensiferm
Although Death metal is mostly rhythm anyway, just like rap.
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