Yellow-green vapors emerge from the ground with a hiss, forming a thick, toxic cloud.

Daily   ✦     Arcane, Evocation, Implement, Poison, Zone
Standard Action      Area burst 5 within 20 squares

Target: Each creature in the burst

Attack: Intelligence vs. Fortitude

Hit: 1d10 + Intelligence modifier poison damage.

Effect: The burst creates a zone that lasts until the end of your next turn. The zone is heavily obscured. Any creature that enters the zone or starts its turn there takes 10 + your Intelligence modifier poison damage (a creature can take this damage only once per turn). As a move action, you can move the zone up to 3 squares.

Sustain Minor: The zone persists until the end of your next turn.

Update (2/17/2012)
Changed in December 2011 updates.

Published in Player's Handbook, page(s) 166, Class Compendium.