[@Shiny Keldeo] So, I was thinking that maybe Julian would have the same background as he did in the comics, but, instead of sticking around for Sonic like he did in the comics after he got his free will back, he goes to fight a war on another planet, which he was able to access through rings (like Sonic did in the 2020 movie), and at the end of said war, he returns back to Mobius, feeling something off about Eggman being gone for so long. 

I don't know if that's a good description, but if you can help me make changes to fit the storyline better, let me know!