You yell a word of ancient origin. Upon hearing it, your foe succumbs to the primeval energy of chaos.

Daily   ✦     Arcane, Implement, Psychic
Standard Action      Ranged 20

Target: One creature

Attack: Charisma vs. Will

Hit: 2d8 + Charisma modifier psychic damage, and ongoing 5 psychic damage (save ends).

Effect: Until the end of the encounter, at the start of each of the target's turns but before it takes any ongoing damage, choose acid, cold, fire, lightning, or thunder. The target gains vulnerable 10 to that damage type until the start of its next turn. If the target is still taking ongoing psychic damage from this power, it gains vulnerable 15 psychic instead.

  Wild Magic: If you rolled an even number on the attack roll, you can apply the effect to a creature within 10 squares of the target instead of to the target. If you rolled an odd number on the attack roll, you can apply the effect to each creature adjacent to the target instead of to the target.

Published in Arcane Power, page(s) 41.