Mana Damper
You negate magical energy ("mana") in your vicinity, making it difficult or impossible for others to cast spells. You can never cast spells yourself, nor can you have any level of Magery.
Each level of Mana Damper (to a maximum of three) reduces the local mana level by one step, but only for you and people or things that you're carrying. For instance, a wizard could throw a fireball at you unhindered, but he would find it difficult to use magic to turn you to stone or read your mind. For details, see Mana.
Special Enhancements
Area Effect: Your ability affects everything in an area centered on you. The first level of Area Effect gives you a radius of one yard. Each level after the first doubles this radius as usual; see Area Effect. +50%/level.
Switchable: You can switch this power off – for instance, to let a friendly wizard affect you or operate within your area of effect. +100%.