Pakellas wrath.

So you thought you could just take your toys and leave, did you? Well,
Pakellas will have none of that - Pakellas will drain your wands, your
rods, your XP evokers, your magic reserves, and even you if there's
nothing else worth draining. Plus, if you abandon Pakellas altogether,
trying to evoke just about anything will occasionally result in a
backlash (the effect will still go through, though, just like Vehumet
and Kiku wrath).