- "So take him! Tear him apart! And keep the bones for yourselves!"
- ―The Dealer
The Dealer is an auctioneer who sells super-villain weapons and artefacts of evil. His mobile location is the Mirror House, where he conducts auctions to the rich and decadent in a dark cult that believes evil is humanity's divine spark. This has made him an enemy of the second Batman.
The Black Mirror
Guiborg first attracts Batman's attention when his sold weapons are involved in a series of murders across Gotham City. Batman disguises himself as a member of the Dealer's dark cult and infiltrates Mirror House, where everyone is required to wear a gas mask. The Dealer immediately exposes him with a sabotaged mask and drugs Batman with hallucinogenic nerve gas. The entire house are commanded to tear Batman apart, and he barely escapes through the violent hallucinations. Batman ambushes the Dealer again on a flight leaving Gotham. He ingests Man-Bat serum to turn himself into a monster, but Batman still beats the crap out of him and the plane goes down during their fight. There's a massive explosion, but the Dealer's body isn't found in the wreckage and he might have escaped. It's later revealed that he was assisted in his Gotham plans by James Gordon Jr..
- Dick Grayson mentions that "Etienne Guiborg" is probably an alias, as the real Étienne Guibourg was a 17th Century priest in France convicted for leading black masses. This means the Dealer is either using an assumed name or his origins are supernatural.
- The Dealer was created by Scott Snyder and Jock, first appearing in Detective Comics #872. However, in the Prime Earth continuity Dealer first appeared as part of the New 52 DC Universe in Nightwing (Volume 3) #17 by Kyle Higgins and Juan Jose Ryp.