Chaos needs to have foot sloggers too. The idea that all Chaos forces are made up of Deamons, Traitor marines and Spawn is a bit sad. The real cloud and fun in a renegade war band is the mutant and beastmen. These are the lackey's that do all the dirty work, ensuring the plans of the champion come to fruition by blasting who ever is in the way. That great tome of Chaos, Slaves to Darkness has an entry in the 40K war bands followers table that I've been mulling over for years.
I then went for some realistic but yucky skin colours on them. Bzzzter got a mauve/blue, Fishface got a normal human skin tone (all the creepier with a face like that) and Grumblechops got a stinky rotten greenish tone.