He flicks an enormous powerful day-duration abjuration loose at her, which promptly settles in.
He didn't use a scroll or item, to be clear; so this person must be at least an eighth-level wizard, or maybe a priest with an unusual domain.
Incidentally, Carissa's Arcane Sight isn't seeing anything magical about him.
"Ri-Dul," he says. "Eighth-circle necromancer. Keltham says you are supposedly recently fourth-circle and supposedly quite good at Spellcraft for that; though he does not know, now, what was truth and what was lie, in that."