After the epic season 3 finale, ‘Invincible’ might be heading to… the underworld?

A chaotic, carnage-filled finale

The Season 3 finale was peak but TRAUMATIZING my god 😭 #Invincible pic.twitter.com/hkUuUnLet5

— sabrina 🦇 (@nightwaynes) March 13, 2025

Season 3 wrapped up in a typically violent fashion, delivering one of the most gruesome battles in the series so far. After barely surviving the Invincible War, where Mark had to fight evil versions of himself from different realities, he found himself facing an even deadlier foe: Conquest. Voiced by Jeffrey Dean Morgan, this grizzled, battle-hardened Viltrumite arrived on Earth with one goal: punish Mark for failing to prepare the planet for a Viltrumite takeover. What followed was nearly 30 minutes of absolute carnage. Mark, alongside his brother Oliver and Atom Eve, barely managed to take down Conquest. 

In a moment of raw, brutal strength, Mark let his Viltrumite instincts take over, using his own skull to crush his enemy’s head. It was a moment that left fans both horrified and exhilarated. But as we’ve learned by now, nothing is ever that simple in Invincible. Despite Mark telling Cecil Stedman to burn Conquest’s body, the leader of the Global Defense Agency had other plans. Instead of disposing of the powerful Viltrumite, Cecil secretly preserved his body, planning to interrogate him about the Viltrum Empire’s next moves once he wakes up. And yes, according to series creator Robert Kirkman, he will wake up.

In an interview with Entertainment Weekly, Kirkman confirmed that Conquest is not dead. He also strongly hinted at a future interrogation scene between him and Walton Goggins’s Cecil. That means the battle with Conquest might not be over just yet. His return could spell even more trouble for Mark in season 4. However, that wasn’t the only surprise waiting in the finale.

A post-credits highway to hell

Robert Kirkman teased that ‘INVINCIBLE’ Season 4 may include an unused comics storyline where Mark fights the Devil.

“Every superhero story has some chapter where they go to hell and they fight the devil. I never got around to doing anything like that in ‘Invincible’”

(Source:… pic.twitter.com/jSXXeOSh93

— DiscussingFilm (@DiscussingFilm) March 14, 2025

After the credits rolled, fans were treated to a cryptic scene featuring Damien Darkblood, the demon detective who was banished to hell after his investigation into Omni-Man got a little too close to the truth. Now, he’s back, and he’s having a conversation with a sinister devil, voiced by Bruce Campbell. The devil hints at summoning a powerful “surface dweller” to the underworld, which immediately raises one massive question: Is Invincible about to take a trip to the underworld?

Kirkman has since revealed to Variety that this scene is teasing a storyline he never got around to doing in the comics. He pointed out that almost every superhero story eventually explores a trip to the inferno. 

I never got around to doing anything like that in Invincible. I kept getting sidetracked, and there was never a good time. So, it’s entirely possible that we may be doing something like that in the show, and that scene at the end of the episode is setting that up.

So, yes. Mark Grayson might indeed be headed to the underworld. It would be a major departure from Invincible’s usual sci-fi and superhero-driven conflicts, but it could be the kind of twist that keeps the series fresh. The post-credits scene has already sparked plenty of fan excitement. With Conquest still in play, and the possibility of Mark fighting supernatural forces in season 4, Invincible is showing no signs of slowing down. Fans are in for one hell of a ride. Literally.