It is widely accepted that metal is a guitar/bass/drums/vocals genre of music. However, it is of increasing occurrence that metal bands are attempting to mix up and rearrange instrumentation in their music. Instrumental bands are becoming more common, some (black metal especially) bands are composing without the use of a bass guitar, and some adventurous bands like Sun0))) are composing guitar only music. Considering this, would it be possible to compose metal without a single guitar lick, perhaps? Or is this experimentation by virtue not metal at all?