Secret of Reawakening

Heroic Tier
Prerequisite: Wilden, Nature's Aspect racial trait
Benefit: Once per day if you drop to 0 hit points or fewer, you can change your current aspect of nature when you are no longer dying, as if you had taken an extended rest. You also regain the use of your wilden racial power as if you had taken a short rest.

Published in Player's Handbook 3, page(s) 183.