The ancient spirit of the oak knocks your foe to the ground. As you rage, you knock foe after foe down to the earth, then strike them with the earth's fury.

Daily   ✦     Primal, Rage, Weapon
Standard Action      Melee weapon

Target: One creature

Attack: Strength vs. AC

Hit: 3[W] + Strength modifier damage, and you knock the target prone.

Miss: Half damage.

Effect: You enter the rage of the oak hammer. Until the rage ends, whenever you hit a target with a melee attack, you knock that target prone. If that target is already prone, the attack instead deals extra damage equal to your Constitution modifier.

Published in Player's Handbook 2, page(s) 55.