
Peacemaker's Season 2 finale introduced a brand new planet called Salvation, and DC Studios co-CEO James Gunn confirmed that this new location is "incredibly important" to the DCU's future. Following up on the wild Earth-X twist, the highly anticipated finale arrived on HBO Max, and it was filled with emotional character moments, DC Easter eggs, and a wild ending that placed the titular protagonist in an unexpected situation. One of the much-talked-about twists in the Season 2 finale was the introduction of Salvation, a distant and mysterious planet with the same environment as Earth, but it holds many secrets.
Rick Flag Sr. (Frank Grillo) proposed to the United States of America's Secretary of Defense that Salvation will become a metahuman prison, citing that the likes of Arkham Asylum and Belle Reve couldn't contain supervillains anymore. While the Secretary of Defense was hesitant with the idea, Peacemaker Season 2 ended with Rick Flag Sr. kidnapping Christopher Smith to trap him inside Salvation, pointing out that he is the first "volunteer" so that he can test the environment's effects on the human body. This is part of Flag Sr.'s elaborate revenge plot against Peacemaker for killing Rick Flag Jr. in The Suicide Squad.
While Season 2 ended with that mind-blowing cliffhanger, fans haven't seen the last of Salvation in the DCU.
Peacemaker Season 2 Rips Salvation Planet Directly from DC Comics Run, Says James Gunn

Speaking during the official "Peace By Peace: Part Three" featurette attached to the end of Peacemaker Season 2, Episode 8 on HBO Max, DC Studios co-CEO James Gunn and Peacemaker star John Cena shed some light on what lies ahead for the DCU after Salvation's introduction.
Gunn confirmed that leaving Peacemaker stranded on the planet Salvation is "going to be an incredibly important thing" in the DCU's future:
"I'm leaving Peacemaker stranded on the planet Salvation. And that's going to be an incredibly important thing in the future of the DCU."
As for John Cena, the DCU actor described Peacemaker's ending as "pretty crazy" because his character is left "alone in an unfamiliar world:"
"Chris is alone in an unfamiliar world. Which is a pretty crazy ending to a pretty crazy eight episodes."
Gunn continued by saying that the true meaning of Salvation's inclusion in the larger DCU is to help humanity by "sending [villainous metahumans]" into the distant dimension:
"...And we see finally, the presentation of something really important to the DCU as a whole, which is the presentation of Salvation to the Secretary of Defense... And we learn that the reason they found Salvation is not to help humanity in any real way... Well, they're trying to help humanity, but they're helping humanity by sending the metahumans into Salvation. Villainous metahumans, they say, but metahumans. And this does come from the comics."
The DC Studios boss also referenced the Salvation comic book run, noting that Rick Flag and Amanda Waller sent villains to this "other planet where they can't get off." Gunn also noted that Peacemaker Season 2's ending is the "beginning of a part of our larger story in the DCU in this moment:"
"There is a comic called Salvation that is a limited series in which Amanda Waller and Rick Flag say, 'Screw it, there's all these metahumans that keep getting into prison and out of prison. F--k it, we don't care what happens to them. This isn't about justice. We're going to send them to this other planet where they can't get off.' Well that's sort of where we're beginning a part of our larger story in the DCU in this moment."

In DC Comics, Salvation is a direct reference to a seven-issue limited series called Salvation Run, which ran from 2007 to 2008. As a tie-in to the famous Final Crisis event, the story follows a world where various supervillains are captured by the Suicide Squad and imprisoned on a distant planet.

Salvation Run revolves around different factions of supervillains as they attempt to build their own civilization, while others try to get back to Earth. It includes a plethora of iconic DC villains, such as Lex Luthor, Joker, Catwoman, Bane, Bloodsport, Gorilla Grodd, and many others.

Bill Willingham and Lilah Sturges wrote Salvation Run, a story inspired by a concept pitched by Game of Thrones author George R.R. Martin and collaborator John Jos.

Gunn also explained the moment when Peacemaker was abducted by Argus, describing it as Rick Flag Sr.'s "ultimate revenge:"
"We have this last little moment where Peacemaker is abducted wearing his Foxy Shazam t-shirt, of all things, and taken and thrown onto this new world of Salvation, which they've now figured out a way to have it lead directly from the warehouse to the other dimension. They throw him out there saying that he volunteered for this, even though he's not a metahuman, and Rick Flag Sr. gets his ultimate revenge, telling him, 'This is for Ricky, you piece of shit.'"

At the end of the episode, Chris is seen walking around the planet, and he then hears some hellish squeals, indicating that he is not alone. Gunn described those squeals coming "from some sort of beast" while also noting that the planet appears not to be a safe haven after all:
"He walks around. "Reckoning" by The Cruel Intentions starts to play, and although the planet is supposed to be a safe haven, even though they're putting prisoners there, we realize this is not the case because we hear some hellish squeals from some sort of beast all around Peacemaker."
Peacemaker Season 2's ending lived up to Gunn's promise that it would set the direction of the DCU's future, and this wild cliffhanger laid the groundwork for the events of Man of Tomorrow.
How Peacemaker Season 2's Ending Impacts Man of Tomorrow

While the first question in anyone's mind is who will show up to save Peacemaker from Salvation, the larger picture is the crucial role Salvation plays in the DCU's grand scheme of things, leading up to the events of Man of Tomorrow.
DC Studios co-CEO James Gunn has publicly said that Peacemaker Season 2 serves as a prequel to Man of Tomorrow, and its wild ending hints that Salvation will play a big part in the Superman follow-up. Given that the distant dimension/planet is described as a metahuman prison, it would need actual villains to inhabit it, and this could be where Lex Luthor comes into play.
Peacemaker's Season 2 ending confirmed that Rick Flag Sr. and Lex Luthor are now partners, with Flag having all of Lex's trusted personnel from Superman working under him. This could mean that Lex found an unusual ally in his continued vendetta against the Kryptonian hero, and all signs point to the fact that part of his grand plan is to send Superman into Salvation.
By the time Man of Tomorrow starts, there may already be a bunch of villains trapped inside Salvation, meaning that Chris either has newfound allies or enemies on the planet. Knowing that Superman is against putting prisoners in a pocket dimension in the first movie, Lex could find a way to tell him about Salvation, leading to his eventual discovery of the distant planet.
Given that the teaser images for Man of Tomorrow hinted at a potential team-up between Lex Luthor and Superman, Lex's possible plan to put Superman into Salvation could backfire, leading to the emergence of a much dangerous threat that could force them to work together.
In the Salvation Run, it is eventually revealed that the planet is ruled over by the New Gods of Apokolips, specifically DeSaad (a villain seen in Zack Snyder's Justice League), who used the dimension as a training ground for Parademons.
If Gunn decides to faithfully adapt Salvation Run, DeSaad's potential presence could hint that Darkseid is not too far behind, setting him up as the future big bad for the DCU.