Counter

The difficulty of this spell is equal to the spell it is being cast against. When you observe a spell being cast, if you have successfully cast that spell before, you may cast counter as an instant action. The caster must then make a mental saving throw or the spell automatically fails. This spell (as with all counterspells) only works against hard magic.
 * Spell Difficulty: X
 * Spell Duration: Instant
 * Spell Range: Sight
 * Spell Type: Restricted (Counter)

(Notes: This spell is often restricted in setting due to how powerful it is. Generally speaking only mages serving the police know this spell, and the secret is closely guarded. Casting or being taught this spell without proper licensing is often times considered a crime.)