[@Crimson Raven]:

Yes, it's entirely reasonable to have a character who doesn't age. All spirits have that by default, and all beings will stop aging if they reach a certain level of power. But the other parts of your idea don't really work.

First of all, at the end of the previous age of magic, pretty much all mages with any real degree of power participated in the final battle and were wiped out. Theoretically, one could have survived, and stayed hidden during the modern age due to seriously hardcore non-interventionism or something. But I do not want there to have been [i]any[/i] magic or magic users during the modern age, so I can't allow that.

Second, your character could've been like my character Evan, whose soul drifted in the Sea of Chaos for a thousand years before reconstituting itself and regaining consciousness. If your character survived the final battle similar to how Evan did, he could've returned to the world at the end of the modern age, and left Earth on a spaceship with the rest of the rich and powerful humans. And then he could've gained Tech powers too as the Tech side developed. But a backstory like that is way too far-fetched, even compared to my own twinked-out characters. It's theoretically not impossible, but I wouldn't even give something like this to one of my own characters.

In other words, no, you cannot have a character who starts out as both Magi and Tech. You [i]could[/i] play as another survivor from the previous age of magic, but that would require far more in-depth discussions with me.

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On another note, I suggest that the players should find opportunities to have their characters meet up with one another. I could initiate an event that makes PCs run into each other, but I'd rather have you guys do it on your own if possible.