Deathstroke, aka Slade Wilson, is likely coming to the DC Universe, either in the Batman standalone film or, more likely, the Justice League movie. How do we know? Because Ben Affleck tweeted this.
That’s Deathstroke, although he looks nothing like Manu Bennett in Arrow, but the Internet says it’s Deathstroke, so I’ll take the Internet’s word for it. The Internet does not know, however, which movie Deathstroke — a solider turned assassin with superhuman strength and intelligence — will be in, but because Justice League is filming in London right now, most believe it will be that movie, which is also expected to feature Steppenwolf, because a movie with multiple superheroes obviously needs multiple villains because no one ever learns from the mistakes of Spider-Man 3.