Oak Skewer
Druid Attack 13
You conjure a massive spear of oak and skewer your foe with it.
Ranged 10
Target: One creature
Attack: Wisdom vs. Fortitude
Hit: 2d6 + Wisdom modifier damage, and you push the target 3 squares. If the target ends this movement adjacent to a solid obstacle (such as a wall), the target is immobilized until the end of your next turn.
Primal Guardian: Add your Constitution modifier to the number of squares you push the target.
Oak Skewer is a 13th level Druid encounter power. On a hit it pushes the target, and if the target ends adjacent to a wall it immobilizes them. [PrP:45]