2006’s Superman / Batman Annual #1 by Joe Kelly and Ed McGuinness presents a “reimagining” of the moment Clark Kent and Bruce Wayne discovered their secret identities on a cruise. In the opening scene, Deathstroke attempts to assassinate Bruce Wayne, but unbeknownst to Slade Wilson, he was getting mixed up in some multiversal shenanigans involving the Crime Syndicate of the Antimatter Universe.
Whereas Deathstroke was hired to take out Wayne, his Antimatter Universe counterpart arrives on the cruise to save the billionaire playboy. He never gets to say his name, but his snarky attitude and overall look strongly resemble a certain other mercenary-for-hire over at the other Big Two company: Deadpool.
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While Deadpool co-creator Rob Liefeld has often stated that the character was more inspired by G.I. Joe’s Snake Eyes than Deathstroke, later comics have made the connection more apparent. Fellow Deadpool co-creator Fabian Nicieza gave the character the alter ego of “Wade Wilson,” a direct nod to Deathstroke’s real name, Slade Wilson. Of course, Deadpool went on to be further developed by several creators in the years since, creators such as Kelly and McGuinness, who worked on Superman / Batman Annual #1.
Kelly is the writer who truly gave fans the Deadpool they know and love today, and his run with McGuinness on Deadpool’s first ongoing series resulted in some of the very best Deadpool comics of all time. Both creators taking the opportunity to recreate some of that magic in the DC Universe was a nice nod to their previous work, and fans got to see what would happen if Deadpool were to interact with Superman and Batman. It’s even more hilarious to see the no-nonsense Deathstroke get increasingly annoyed with his Antimatter counterpart, at one point claiming he’d rather die than hear the assassin talk anymore.
It's a fun nod - as they say, we wouldn't have a Deadpool movie without Joe Kelly taking Liefeld's character and running with it.