Warning: This article contains spoilers from Invincible season 3, episode 7, “What Have I Done?”

Invincible co-showrunners Robert Kirkman and Simon Racioppa posed questions to the audience at the start of season 3: What are the dangers and benefits of Mark Grayson (Steven Yeun)? Does Earth need guardrails in place against the most powerful individual on the planet, even if he’s on our side? They weren’t easy questions to answer. Characters took sides as the season progressed, but this week’s episode 7, titled “What Have I Done?”, delivers a cataclysmic demonstration of the worst case scenario: what could anyone do if Mark turned against us?

Thus begins the Invincible War. Fans have long waited to see how the show, produced by Skybound Entertainment, adapts this massive event from Kirkman’s comics, which sees Angstrom (Sterling K. Brown) assemble an army of evil Marks from alternate dimensions to lay siege to Earth. All superheroes around the globe, including our Mark, team up for their most brutal fight yet. And then as the dust settles, with huge casualties on both sides, an even larger threat arrives.

In the final minutes of the episode, Conquest, one of the most powerful Viltrumites ever, comes to address Mark’s failure to prep the planet for a Viltrum Empire takeover. It sets the stage for one helluva final battle in the season 3 finale, which drops next week. And as an added surprise, Conquest is not voiced by Jonathan Banks, as most fans and media outlets presumed. He’s voiced by Kirkman’s longtime friend Jeffrey Dean Morgan.

“The only reason we survive that [Invincible War] is because of Mark. So he’s both the threat and our salvation,” Racioppa tells Entertainment Weekly in an exclusive interview breaking down the seventh episode. “There’s no white or black, there’s no easy answer to these questions. There’s this huge morass of gray that both Mark and Cecil [Walton Goggins], and most of our characters, exist in. If you came into the series hoping for easy answers, that’s not what the show is.”

The Invincible War

Yeun had quite the task on his hands. The Minari Oscar nominee and Beef Emmy winner voices 18 different versions of Mark over the course of episode 7. Racioppa calls one of them “Mohawk Invincible,” whom he describes as “just such an asshole.” He also refers to “laid back, but super evil” Invincible and “chill bro” Invincible over the course of our conversation.

“It was trying to find something that each of the Invincibles had that Steven could hook onto and then build from,” the showrunner says. “A lot of it came from Steven, as well, to give you 18 characters [and] try to make them all feel different in an hour of TV. It’s technically less than an hour. I think it’s astounding.”

“We were spitballing in the booth a lot,” Yeun, now on the press tour for his movie Mickey 17, writes to EW over email. “They would tell me what the character was like, and I would just try some things out and they would give me feedback. For me, it was most about understanding the specific psyche of the character that helped me.”

Given how big the Invincible War is in the comics, the creators discussed potentially splitting up the adaptation over more than one episode. Though, those considerations quickly fizzled out. Racioppa didn’t want to be accused of bloat. “I’m also of the mind of just, keep it moving,” he remarks.

He jokes they pulled off “a whole Marvel Phase 1, 2, and 3 in one episode” by the time they finished adapting the Invincible War arc, but despite the grandiosity, it’s still very much about Mark. In one particular scene, prior to the battle between Angstrom and our Mark, the remaining evil Invincible variants acknowledge that they’re all essentially the same person. If season 1 was all about Mark wanting to become his father and season 2 was Mark becoming terrified of becoming his father, season 3, Racioppa explains, is Mark “standing on his own feet and discovering who he needs to be, who he wants to be as a hero, and what that entails from his perspective.”

“We put him through the ringer 100 different ways in this season,” the showrunner admits.

“What Have I Done?” still remains true to the main beats of the comic book storyline, including the death of Rex Splode (Jason Mantzoukas), who sacrifices himself by exploding his own skeleton to take out one of the Invincibles. The team even recreated specific comic book panels from original artist Ryan Ottley. The elements they couldn’t factor in, however, were the added guests.

The comics featured other characters from across the IP aisle, such as Spawn and Witchblade. TV, however, makes those kinds of crossovers a bit more complicated. “I don’t think anyone on the show would not want that to happen,” Racioppa comments, “but there’s just so many rights issues. It is a lot easier in comics than it is in television. When Robert was writing these books years ago, it was a lot easier. I think everything is now so controlled… It’s a bit of a nightmare.”

And speaking of nightmares…

Conquest

For Morgan, voicing Conquest in the studio may have been some of the physically hardest hours of his acting life. “I don’t know what it is about being in a [recording] booth and trying to destroy the world,” he comments playfully during a conversation with Kirkman, “but it’s really physically hard.”

As Mark attempts to clean up the wreckage left in the wake of his evil selves, Conquest flies down to confront Earth’s chief hero. Both are seen hurdling towards each other, fists outstretched, before the screen cuts to black. Kirkman says he’s been thinking of Morgan for this villain role “probably since the beginning of the show’s existence…. Conquest needs a lot of nuance. There’s a tremendous amount of personality there, even though he is this giant, powerful brute that’s just wrecking things. And I knew Jeffrey could bring that.”

The meta nature of casting Morgan also felt “too great not to do,” Kirkman adds. Fans of The Walking Dead will never forget how the actor, playing Negan, bludgeoned Yeun’s Glenn to death with a barbed baseball bat. The two stars now face each other on screen once again, but in different roles. “We certainly couldn’t ignore that fact… All I can say is that it is always a pleasure and honor to work with Jeffrey Dean Morgan,” Yeun writes in an email. “He is a great actor and human and also knows how to play a tremendous heel.”

“I was just thrilled to get to be a part of it and give Steven his chance at redemption,” Morgan quips. He acknowledges certain similarities between Negan and Conquest, but he wanted to be “as far away” from that as possible, he says. “I was trying to be aware of just voice inflection. It’s so easy for me to get into Negan mode after this many years.”

Regarding all the fan theories about Banks voicing Conquest, Kirkman and Racioppa knew what they were doing. “I am acutely aware that once you are familiar with the comics, certain casting announcements, basically you go, ‘Well, that’s going to fall in this episode,'” Kirkman remarks. “It’s kind of like giving you too many pieces of the puzzle.” So they decided to hold that particular name back from press releases. Then…

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Morgan himself accidentally put that puzzle in jeopardy. In January 2023, Morgan posted a photo of himself with the Invincible comics with the caption, “Doing a little reading, thanks to #robertkirkman.” He also tagged the official Invincible show handle. “Robert texted me, he’s like, ‘What the f— dude?! Whatcha doing? Because it just [put] the whole fandom in an uproar,” the actor recalls. “Like, ‘What could he be doing?’ ‘Are they doing the film now?’ It was crazy for a little bit there. So I was told in no uncertain terms, ‘Maybe just cool it with Invincible, just chill out for a minute.'”

That talk did die down, though. Everyone involved now hopes Morgan ended up surprising the fandom with Conquest’s arrival. What does this now all mean for the season finale incursion?

“At the end of 307, Mark is at his absolute lowest,” Kirkman teases. “He has seen other versions of himself decimate the planet. Everyone is turned against him. He is participating in the rebuilding effort, but he feels more guilt than he has ever felt in his life. And Conquest shows up. So he’s in this unique head space. He’s backed into a corner. The world is already in shambles, and Cecil calls [Conquest] ‘Mr. 10 Times Worse.’ We’ve been hinting at this character’s arrival since season 2, when Anissa warned that he was going to be coming, and now he’s here. So it’s going to get even worse somehow.”

The Invincible season 3 finale drops March 13 on Prime Video.