Lou Fine cover pencil and ink credits confirmed by one-time owner of the original art, Roger Hill, and confirmed to him by a conversation he had with Will Eisner (January 5, 2010).
Fletcher "Flint" Baker (introduction, origin); Harry Parks (introduction); Phil Godwin (introduction); Cliff Grant (introduction, death); Mimi Wilson (introduction); King of Mars (introduction); Princess Viga; Sarko (villain, introduction, death)
Auro [Hardwich] (introduction, origin); Professor John Hardwich (introduction, death, Auro's father); Mrs. John Hardwich (introduction, death, Auro's mother); Martha Gale; King of Neptune (villain, introduction)