Ajani Goldmane

+1: You gain 2 life.
−1: Put a +1/+1 counter on each creature you control. Those creatures gain vigilance until end of turn.
−6: Create a white Avatar creature token. It has "This creature's power and toughness are each equal to your life total."

Serra Ascendant

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
As long as you have 30 or more life, Serra Ascendant gets +5/+5 and has flying.

Martyr of Sands

{1}, Reveal X white cards from your hand, Sacrifice Martyr of Sands: You gain three times X life.

Soul Warden

Whenever another creature enters, you gain 1 life.

Soul's Attendant

Whenever another creature enters, you may gain 1 life.