Although the first season of Peacemaker is still filming and won't release until next year, writer/director James Gunn is already thinking about future seasons of the show. On Twitter, he shared an article about his future projects and said, "I cannot tell you how much I appreciate the folks at @hbomax. Their humanity & support of my creative vision on the #Peacemaker show - despite numerous obstacles along the way - is beyond compare. I only pray that the cast, crew & I are equally good partners."
A fan commented on it asking if there were any DC characters that didn't make the cut for the first season of Peacemaker. Gunn responded by saying, "Yes. Saving someone for season two..."
The Peacemaker series will be a spinoff of Gunn's upcoming film The Suicide Squad which releases in theaters and HBO Max on August 6, 2021. John Cena will portray Peacemaker in both the film and the series, but it is not known whether the show will be a prequel or sequel to the movie. Gunn has consistently stated that The Suicide Squad will be very deadly and kill off most of the characters, so John Cena's Peacemaker has a good chance of biting it. However, if the Peacemaker series is in fact a prequel, it's interesting that Gunn is already planning on a Season 2. I predict that the revelation of a potential Season 2 implies that Peacemaker will survive The Suicide Squad, but Gunn is known for his narrative red herrings.
As for what character he's teasing in his tweet, it's impossible to know at this point. There are tons of big name DC characters that Peacemaker has interacted with in the comics. Characters like Blue Beetle, Nightwing, The Question, Captain Atom, and even one of the Watchmen could be some fun guesses - all of which Peacemaker has a history with. My guess is that Gunn is thinking of a pretty well known figure, but chose to save them for the second season in case HBO Max wanted to go in a different direction.
James Gunn has apparently found his filmmaking niche as his slate is chock full of superhero projects. The Suicide Squad releases in August, Peacemaker is currently filming, Guardians of the Galaxy vol. 3 and the Guardians Holiday Special begin filming later this year, and now Peacemaker Season 2 is potentially on the table. Additionally, Gunn has expressed his desire to do more films and shows set in the DC universe, specifically with Margot Robbie's Harley Quinn. A potential Harley Quinn/Poison Ivy film has been pitched, and James Gunn's name has been in the middle of some of those rumors. It's possible that Gunn has finally found his home with the DCEU.
Peacemaker will star John Cena as Peacemaker, Steve Agee as John Economos (reprising his role from the upcoming The Suicide Squad), Danielle Brooks as Leota Adebayo, Robert Patrick as Auggie Smith, Jennifer Holland as Emilia Harcourt, Chukwudi Iwuji as Clemson Murn, Chris Conrad as Adrian Chase/The Vigilante, and Christopher Heyerdahl as Captain Locke. Peacemaker will premiere on HBO Max in January 2022.