Arven has a somewhat mechanical appearance, having presumably metal skin, skinny limbs, and sharp tipped legs. His face is vacant besides a black strip, possibly his eyesight, and a long fin on the back of his head. He is described to be extremely fast, and because of it, is very fast thinking which lead him to build without stopping to realize what he had built. This carelessness, however, seemed to work in his favor; he seemed to be able to create perfect environments, intelligent lifeforms.