Essence Warden

Oracle Text

Whenever another creature enters the battlefield, you gain 1 life.

Card Rulings

10/4/2004 Does not trigger on a card on the battlefield being changed into a creature.
10/4/2004 The ability will not trigger on itself entering the battlefield, but it will trigger on any other creature that is put onto the battlefield at the same time.
2/1/2007 This is the timeshifted version of Soul Warden.