Your attack sends the primal energy of earth flowing into your enemy, slowing its movement.

At-Will   ✦     Primal, Weapon
Standard Action      Melee weapon

Target: One creature

Attack: Strength vs. AC

Hit: 1[W] + Strength modifier damage, and the target is slowed until the end of your next turn.
Level 21: 2[W] + Strength modifier damage.

Published in Player's Handbook 2, page(s) 154.