The Number Twelve Looks Like You
Behold... the Arctopus
The Locust
Okay I would say that these have been missed so far. There are other genres you could label these bands as, however I think avant-garde also suits them.
Agalloch
bad acid trip
fantomas
farmakon
devin townsend
Kekal
Lux occulta
Nuclear Rabbit
Polkadot Cadaver
Sculptured
Subterranean Masquerade
Okay I'll stop....
Fact: 99% of the bands that call themselves Avante-Garde suck ASS.