No sooner has Rozemyne’s fourth year at the Royal Academy begun than she ends up somewhere unexpected. How will the saint respond when an incident in Ahrensbach leaves everyone else feeling defeated?
It is not explained, but it appears to be the same thing that Myne did to call for Lutz, while bound up by the trombe.
Though I would expect that Ferdinand cast that spell deliberately, rather than instinctively like Myne did, and was further aided by him wearing one of her charms, still filled with some of her mana.
I wonder if it might be because he charged both Ehrenfest's and Ahrensbach's foundations and thus some of his mana is in both sides of the duchy barrier between them.