Besides his own title, Proof appeared in 2008's Image Monster Pile-Up, a one-shot anthology comic that also featured The Astounding Wolf-Man, The Perhapanauts, and Firebreather.

The plot also details the transfer of Ginger Brown, a young female agent, from the F.B.I to a secret organization called The Lodge.

Brown's first case with The Lodge concerns El Chupacabra, a monster who masquerades as a human by wearing the skin of its victims.

and features dual main plots: Ginger and Elvis journey to New York City to find Joe the golem, while Proof investigates sightings of condorlike thunderbirds in rural Illinois.

The story delves into Proof's past with his so-called "brother" Mi-Chen Po, and the plot is loosely based on the history of Julia Pastrana.