He is very thin with a receding hairline. He has a kind of sneaky appearance.
In SlugTerra, Gar Revelle has a history of failed explorations to the Burning World. He first appears in "A Distant Shore" where he tries to recruit volunteers to go with him on his latest expedition, which catches the attention of Eli Shane. Lured by the promise of fame and fortune, many slugslingers answer the call, but Eli is more interested in the book in which Gar possesses.
It is later learned to be the journal of his great-uncle Jimmo Shane, which contains coded directions for reaching Earth's surface. Knowing that the two worlds can never mix, Eli manages to steal the book and later destroys it, after accidentally revealing the code's cipher to Gar.
Following the book's destruction and subsequent disbanding of the exploration team, Gar is, once more, ridiculed as a fraud.