Wind prison
druid attack 1
Target: one creature
Attack: Wisdom vs. Reflex
Hit: 2d10 + Wisdom modifier damage.
Effect: The target grants combat advantage until it moves or until the end of the encounter. The first time the target moves before the end of the encounter, each enemy within 5 squares of the target is knocked prone.
Wind prison is a 1st-level druid daily attack power. On a hit, it deals damage to the target. Whether it hits or misses, it also causes a target to grant combat advantage until it moves or until the end of the encounter. If the target moves before the end of the encounter, enemies within 5 squares of it are knocked prone.[PH2:86]