All strength is doomed to crumble. Your spell's shrieking assault demonstrates the point.

Encounter   ✦     Arcane, Implement, Psychic
Standard Action      Ranged 20

Target: One creature

Attack: Charisma vs. Fortitude. If the target has more hit points than you do when you attack, you gain a +2 power bonus to the attack roll.

Hit: 4d8 + Charisma modifier psychic damage.

Dark Pact: The power bonus to attack rolls against a target that has more hit points than you do is +4.

Published in Forgotten Realms Player's Guide, page(s) 40.