Oddly enough, I'm seeing this AFTER the 2nd part, which I just saw today. So, for me, this was kind of like watching a flashback. In fact, I think it works better as a flashback. Because by itself, it raises more questions than it answers... such as "How is the average guy able to hold his own against supervillain X?"
So now we're going to need an origin chapter for the non-supervillain. Which is easy: you can use the same bar scene and just loop in some new dialogue, then have the first guy go "Wait.. I was the top-ranked student in supervillain school.. how DID you hold your own against me?" and the second guy can spend a minute or two bantering about some made-up fake origin that's an obvious parody of supervillain school, and then we flashback to the real story, a 3-second clip where it turns out he's a God, or Super-Saiyan, or whatever. :)
It will definitely involve the relic... that's just how these things roll. :)