CAPTAIN FUTURE VOL 2 NO 2 (1941)
This series of pulp novels features a hero named Captain Future, with most of the stories written by Edmond Hamilton, who would later move on to comics. In this issue, he introduces an amorphous shape-changing blob named Oog, which he would adapt into Chameleon Boy's pet, Proty, when he took over the Legion. This story also mentions a Chameleon Man and the Pleasure Planet, a gambling asteroid akin to Ventura, home of the Luck Lords. See more about the genesis of Proty here.