Gavren nods, and readjusts to her dragon form, as soon as she's out of the way of the portal. Serena simply laughs, at his question. "Because I'm not stepping through it all the way, of course," she explains, then elaborates at his presumed look of confusion. "I know it's not much of a difference, compared to someone like yourself, but the further I get from my home plane, and, given that it's now attached to your realm, in the Astral, the more power I have to leave behind, barring those exceptional circumstances you mentioned. You're different, of course, because you have two 'natural' locations, as you're still a part of the Material, so you're never more than a step away from home, unlike me, who's now three steps removed. It's worse for those in the Outer planes, as they're four steps away, and lose the majority of their power. Still incredibly powerful compared to anything mortal, of course, but restricted more than elsewhere."