[Damian doesn't answer the last part on purpose. It's a little bit of empathy: no one else should have to do it. And it's also a little bit of pride: he can change it.]

There's different ways. Metahuman or alien powers, technologically advanced gates that open a hole in space-time. Todd is from my universe, but technically from a different timeline. Not in the sense of things are different, but in the sense he is from my universe's past.

Anyone can be pulled through, even multiple people from the same universe.