Eventually he becomes so strong, Zanz steps in.
Zanzarino wasn't even born at that time. No, I absolutely do NOT want to make Zanz more than he's supposed to be, since this isn't Elements so Zanz isn't God here. I do not want to let this one go, since it's a part of my original idea when I started the game.
After a while, he goes batshit insane, and just becomes and interdimensional pirate, learning and taking what he wants and destroying as he goes.
You can't become some sort of Anti-God just by "taking and learning". I mean, really, where can you learn to
eat worlds?
I did not shoot down your idea about Alan, so in return I would prefer if you accept my idea of how Alan became God/Annihilus after absorbing Deus ex Machina and the Void.
Maybe the Deus ex Machina is a "reality divergence machine", a device that
creates parallel universes. Before Alan invented that machine, there was only one universe, but after that everyone went to their respective ideal parallel universes. Alan thought that if he destroyed the machine, all the parallel universes would merge back together, but he was wrong. Due to the repeated reality splitting, Alan's original universe was already unstable, and the Deus ex Machina was the only thing holding it together. When Alan destroys the machine, his original universe completely collapses, leaving a Void behind. Alan absorbed the Void and Divine powers, turned into God, and started to visit other universes to try to convince his people to come back. He became insane after everybody refused, and half of him wanted to devour all the worlds and merge them back to one. Then, he used the "reality divergence" ability on himself, and split into God and Annihilus.
Also, can you stop narrating as Annihilus for now? I mean, I don't want to have too much emphasis on him right now.