Rune of Rupture

Description (Talon)
Rune of Rupture Activated! Draining 10 MP/second

This rune will channel your mana into a disruptive form, allowing you to strike out at magical abilities. It's excellent for breaking enchantments, blocking spells more effectively, and cutting through magical armor. It can even destroy objects you can't physically touch - illusions, in particular, but also scrying spells, magical light… anything you can see and that has a location, you can destroy. Of course, doing so requires an expenditure of mana in direct proportion to the power and mana of your opponent's spell… if you encounter someone far more powerful than you, even a mundane spell could leave you exhausted to dispel it.

Reference
Chapter 137 "William Shakespeare"