This can be later in the series, like in another season or something, and if you approve I'll also animate it.
Kcetza (I haven't really thought about how) falls into the Void. There, he finds the core (were Void sacrifices himself in the Unfamous), and Kcetza touches the core in awe. He then gets absorbed into the core, where he changes. For example, as you see on the art, his white eye turns purple, and he undergoes a lot of pain. He sees the future where Void betrays him, and a nuclear explosion happens in the Void, because he's in the core. Now, Kcetza has some of Void’s powers, but weakened. He teleports back to Scratch, fights Void, blah blah blah, what do you think?
