They returned the same way they'd left.
A temporary gate carved open the fabric of space with a shimmer of silver light, and Kain, still feeling vaguely sick from the last one, sighed before stepping through. Lord Storm, of course, didn't hesitate—he walked forward with the calm finality of a man who'd never known teleportation nausea.
On the other side, a familiar breeze greeted them. They were back in the same quiet, secluded stone courtyard they'd left Serena in—a private pocket near the central plaza's edge, cordoned off with an inconspicuous array of disposable devices that looked like small balls with sigils carved into them—likely warding off any civilians that happen to wander this way. When Kain and Serena's father returned, the glowing balls all faded and then disintegrated—clearly having a mechanism set up to detect when a second teleportation to the location occurs.