Advisors are large larvae-like creatures which are virtually featureless, with no visible eyes, ears or limbs, though they do possess an eye-like mechanical device attached to the left side of their heads, and detachable mechanical arms. Their faces are covered by a form of respirator, which is able to lift to reveal a mouth-like orifice from which extends a long flexible proboscis. With this, they can examine objects, or attack and kill enemies. Advisors appear to be feeding upon their victim during their attacks. It is implied that Advisors are the original master race behind the Combine, with the Earth administrator Wallace Breen answering directly to them. Although Advisors are usually seen in protective pods guarded by Combine soldiers, they also possess telekinetic powers with which they are able to float through the air and immobilize enemies so that their proboscis can examine their victims without interference. Their appearance was based on the Guild Navigators from the film "Dune".