When your projectile hits, primal spirits pull at your target, slowing it down.

Encounter   ✦     Primal, Weapon
Standard Action      Area burst 1 within weapon range

Target: Each enemy in the burst

Attack: Wisdom vs. Will

Hit: 1[W] + 1d8 + Wisdom modifier damage, and the target is slowed until the end of your next turn.

Published in Player's Handbook 3, page(s) 132.