Warning: Contains SPOILERS for Invincible season 3, episode 8!
Although Omni-Man beat Invincible in season 1, stronger than the evil Invincible variants that appear in season 3's Invincible War storyline. Now, Mark Grayson may be even stronger than Omni-Man, although he still has to take on a Viltrumite that overpowers him for most of their fight in the Invincible season 3 finale.
Invincible season 3 has come to a close, with Mark having to deal with back-to-back fights with alternate versions of Invincible and the deadly Viltrumite, Conquest. Invincible season 3, episode 7 saw Angstrom Levy bring an army of evil Mark Graysons to Mark's home dimension, with him having to face several of them on his own. During the clean-up effort, Conquest appeared, with him threatening to kill Mark for his failure to prepare Earth for Viltrumite invasion. Despite their fight being destructive, Mark eventually defeated Conquest.
Mark's Fight Against Conquest Strongly Suggests He's More Powerful Than Omni-Man After Invincible Season 3
At Least Cecil Thinks So
When Conquest arrives on Earth in Invincible season 3, everybody panics. While Mark is dealing with the Viltrumite threat, Cecil is working from the sideline to assist him. While having a conversation about Invincible's chances, Cecil mentions that he believes even Omni-Man would have lost to Conquest. While this speaks to how powerful Conquest is, the battle's result also speaks to how strong Mark has become.

Invincible Confirms Why Cecil Is Secretly One Of The Show's Most Powerful Characters
Despite Invincible having plenty of strong heroes, Cecil has proven to be surprisingly powerful, and season 3's Invincible War just confirmed it.
Since Mark eventually beats Conquest, this would mean that Mark is stronger than Omni-Man if Omni-Man would have lost to Conquest. While Mark did get help from Atom Eve, Omni-Man would have most likely gotten help from the Guardians of the Globe if he were still a hero, meaning that it is a bit hard to compare the two. In Cecil's eyes, however, his beliefs about Omni-Man's chances means that he must now see Mark as stronger than his father.
Omni-Man Was Never One Of Invincible's Strongest Viltrumites
There Were Always Stronger Ones
While Omni-Man's Viltrumite DNA makes him stronger than almost any Earthling, he was never one of the Invincible universe's strongest Viltrumites. Omni-Man is definitely the strongest Viltrumite seen in season 1, as he is far stronger than Mark Grayson at the time. However, the introduction of later Viltrumites hurts his reputation.

What Happens To Invincible's Evil Mark Graysons After Season 3, Episode 7
Invincible's evil variants of Mark Graysons are abruptly shunted out of the episode before the climax, setting up their potential return.
Conquest has always been stronger than Nolan, meaning that there was always someone out there who could beat Omni-Man. Although Thragg hasn't yet been introduced, he is stronger than Nolan as well, meaning that he could have beaten Omni-Man if he came to Earth. While Nolan is respected for his strenght within the Viltrum Empire, he was still never as strong as these other two Invincible characters.

- Created by
- Robert Kirkman
- First TV Show
- Invincible
- Cast
- Gillian Jacobs, Andrew Rannells
- Video Game(s)
- Invincible: Guarding the Globe
- Character(s)
- Invincible, Debbie Grayson, Atom Eve, William Clockwell, Omni-Man