Invincible co-creator Robert Kirkman revealed that Season 4 will introduce a brand new story not seen in the comics.
Invincible's third season adapted the comics run by Robert Kirkman, Cory Walker, and Ryan Ottley closely, but the post-credits scene of its finale featured a returning character, leading to a brand new story in Season 4.
I wrote the fourth episode.
According to Robert Kirkman, this original story will take place during Season 4's fourth episode.
Author's summary: Invincible Season 4 has new story.