Your howl of victory shakes your enemies to the core, as they know your blood thirst is not yet quenched.

Encounter   ✦     Fear, Primal
Free Action      Close burst 5

Trigger: Your attack reduces an enemy to 0 hit points

Target: Each enemy in the burst

Effect: Each target takes a -2 penalty to all defenses until the end of your next turn.

Published in Player's Handbook 2, page(s) 50.