 What are Hathaway and Marnagan's physiques like?
Hathaway only knew he was picked up and hurled against a lever-bank, and that Marnagan wasn't long in following, swearing loud words. Hathaway felt himself grabbed; he and Marnagan rattled around—human dice in a croupier's cup. They stood in the middle of a pocked, time-eroded meteor plain that stretched off, dipping down into silent indigo and a rash of stars. Immense crimson beasts with numerous legs and gnashing mandibles, brown-black creatures, some tubular and fat, others like thin white poisonous whips slashing along in the air. Hathaway made it first, Marnagan bellowing just behind him. Super-gravity and a couple of well-tossed meteors.
 Both of their appearances are described to some degree, and Marnagan is often described as being a large presence.
 There isn't much discussion about how either person looks at all.  Marnagan is consistently described as feeble in comparison to Hathaway.  Both of their appearances are described to some degree, and Marnagan is often described as being a large presence.  Both are each regularly described as having similar builds.