Ever since War for the Planet of the Apes' Matt Reeves succeeded Ben Affleck as The Batman's director and confirmed that he's starting from scratch on the script, there's been speculation about whether or not Deathstroke will be kept as the movie's main antagonist. It was announced last year that Joe Manganiello would play Slade Wilson, but since Reeves' boarded the Caped Crusader's project, the assassin's cinematic future has been called into question. Now thanks to new information regarding Manu Bennett's Deathstroke on Arrow, it's implied that the reason the DC CW series was able to use the character again was because the DC films division no longer had anything planned for him. When recently asked about how Arrow was recently able to bring back Slade, executive producer Marc Guggenheim said the following:
It was actually a function of...DC, like I said, they control these characters, and we went through a period where DC was like, 'We've got plans for Deathstroke that don't involve Arrow.' That changed at the end of this year.
When taking into account how Joe Manganiello was cast as Deathstroke last year, the explanation Marc Guggenheim provided to Collider seems to indicate that these "plans" the DC brass had in the works was including Slade Wilson in The Batman movie. However, a lot has changed with that movie since the beginning of 2017, and evidently restrictions have loosened to the point that DC was willing to let Guggenheim and the Arrow team finally bring back their version of Slade. This still isn't official confirmation that we won't see Deathstroke in The Batman, but it certainly doesn't bode well for those who've been eager to see him clash with the Caped Crusader in a theatrical setting.
The timeline for The Batman's changes does line up with Arrow's schedule earlier this year. Ben Affleck dropped out as the movie's director in January, and Matt Reeves was hired to replace him in late February. This was likely around the same time that the Arrow team started drafting the final episodes of Season 5. Thanks to Guggenheim getting the go ahead, he was able to throw Slade Wilson into Season 5's final two episodes and bring him back for a few upcoming Season 6 episodes (which will include an arc involving his son, Joe). So for all the Deathstroke fans out there, you can see Manu Bennett's version continue to develop on the small screen later this year.
As for Joe Manganiello's Deathstroke, his future remains uncertain, although the actor says he's been informed about what's happening on that front. With Matt Reeves still in the early stages of writing The Batman, it will be a while until we learn what the movie will be about, although Reeves has expressed interest in telling a "noir-driven, detective" story. Such a tale may not call for a one-eyed, physically-enhanced mercenary who loves using swords.
The Batman is among the many DCEU projects that are in active development, so keep checking back with CinemaBlend for more updates on how it's coming along.