how could the MC even go about beating deus, even when we reach evolution 5 how do you beat a guy who can go back in time at will and kill your past self when your at a lower evolution
All the MC would have to do is become a living memory and eat away at Deus from within his mind or completely remove his memories during said encounter. You might say his Future Sight would pick it up but that's not necessarily true. As far as Deus would know, that future ends in darkness. He won't know the cause because it can't be detected. He would just know that he was fighting the MC there and it just ended with the MC disappearing before completely going dark.
Even if he detected or resisted the memory wiping somehow and decided to go back in time, he would be taking the MC with him in the process. Since you know, he's within Deus mind. There's really no way to prevent it. Deus future sight ability isn't all knowing either as he didn't know that Origin MC would sync himself to his higher plane, which is why he had no choice but to go back in time. It's also likely that Deus views the future from his own point of view of the events and not like an outside observer. So a hypothetical Living Memory attack would screw Deus completely.
This is all speculation by the way and under the assumption that Deus Time powers are still limited to his Level 4 self here. I'm not sure how far the MC's Memory Trait will go by Level 5 but I've came up with several different applications for it, like limited teleportation and so on. I have a post here somewhere for it all. I should update it with new info and names. This is why I find the Memory Trait so fascinating. You can be extremely creative with it and come up with insane stuff.