Deathstroke will, in fact, be the main antagonist of the Batman standalone movie, The Wrap has exclusively learned from an individual with knowledge of the situation.
Ben Affleck, the actor who plays the Dark Knight posted a cryptic tweet of the new villain walking toward the camera in very cinematic fashion, which sent fanboys into a frenzy of speculation.
Deathstroke was created by Marv Wolfman and George Perez. He is a mercenary and assassin who first appeared in “The New Teen Titans” #2 back in 1980. Wizard magazine rated him the 24th greatest villain of all time.
Also, in 2009, Deathstroke was ranked as IGN’s 32nd greatest comic book villain of all time. Deathstroke, or commonly referred to as Deathstroke the Terminator or simply Slade, is known to be the greatest assassin in all of DC Comics. He has encountered Batman on several occasions in the comics.
Their first encounter was in the 1991 Deathstroke standalone DC comic in the story arc “City of Assassins” where Deathstroke pounded Batman to a bloody pulp.
— Ben Affleck (@BenAffleck) August 29, 2016
Credit: The Wrap