Quote Originally Posted by The Glyphstone View Post
It's an excellent defensive spell for, say, a Summoner wizard or a buffzard with allies. As an offensive anti-caster tool, it sucks horribly.
It is also perfect for enchanting a pair of manacles or prison door with.

Also, once you've captured him, deprive him of all possessions, including spellbooks, holy symbols, material components, his tongue, and his hands. Check his skin for tattoos as well. Remove them, if he has any.

I imagine there are ways to bypass these measures, but only with certain feats can certain casters make use of existing spells, assuming they can also bypass the anti-magic field. Spell-preparing casters (wizards, archivists, etc.) can also no longer get any new ones.