Slippery oil floods the ground under your foes, sending them tumbling to the ground.

Daily   ✦     Arcane, Evocation, Implement, Zone
Standard Action      Area burst 2 within 10

Effect: The burst creates a zone of slick grease that covers all horizontal surfaces until the end of the encounter. The zone is difficult terrain. You can use the Grease Attack power, using a square within the zone as the origin square.

Update (10/18/2011)
Updated in Wizard Schools article.

Slippery oil floods the ground under your foes, sending them tumbling to the ground.

Daily ✦     Arcane, Implement, Zone
Free Action      Close burst 1

Requirement: The Grease power must be active to use this power.

Trigger: A creature enters the zone

Target: The triggering creature in the burst

Attack: Intelligence vs. Reflex

Hit: You knock the target prone.

Miss: You slide the target 2 squares. This movement does not trigger this power's attack.

Published in Arcane Power, page(s) 102.