On his blog, Chris Weston posts art from a rejected Elseworlds pitch for DC called Batman: Aces High, Jokers Wild. Set during World War I, the story featured a teamup between the Dark Knight and Enemy Ace:
It features Bruce Wayne as volunteer a pilot in Lescadrille Lafayette, swearing vengeance on the Hun after his parents went down with the Lusitania. The Joker’s in there too as a German pilot known as the “Killer Clown”, his face twisted by hideous duelling scars… and of course his squadron is nick-named “The Flying Circus” and are decked out in garish colours. Two Face is a French pilot horrifically burnt in a crash. And chucked into the mix is Enemy Ace, who becomes increasingly uncomfortable during the course of the book with “The Killer Clown’s” un-chivalrous conduct in the air, and, more disturbingly, his torture of captured airmen.
“I thought it was a great idea,” Weston writes. “DC didn’t agree.”
More art can be seen at the link.