Although not holding rank, this strong man treads fine rocks.
Tough Guy, Shattered Man, Dungeon Man, Gerardo/George Montague
Although not holding rank, - They don't have any official rank, such as Captain, Royal, or I'm-too-cool-for-school.
this strong man - They're all pretty buff/huge.
treads fine rocks. - Fine rocks is another way of describing sand, and all of them run around on it.