Healer's Hawk

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Griffin Aerie

At the beginning of your end step, if you gained 3 or more life this turn, create a 2/2 white Griffin creature token with flying.

Light of Promise

Enchant creature
Enchanted creature has "Whenever you gain life, put that many +1/+1 counters on this creature."

Plains

Daxos, Blessed by the Sun

Daxos's toughness is equal to your devotion to white. (Each {W} in the mana costs of permanents you control counts toward your devotion to white.)
Whenever another creature you control enters or dies, you gain 1 life.

Ajani's Pridemate

Whenever you gain life, put a +1/+1 counter on this creature.

Archon of Sun's Grace

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Pegasus creatures you control have lifelink.
Constellation — Whenever an enchantment you control enters, create a 2/2 white Pegasus creature token with flying.

Linden, the Steadfast Queen

Vigilance (Attacking doesn't cause this creature to tap.)
Whenever a white creature you control attacks, you gain 1 life.

Speaker of the Heavens

Vigilance, lifelink (Attacking doesn't cause this creature to tap. Damage dealt by this creature also causes you to gain that much life.)
{T}: Create a 4/4 white Angel creature token with flying. Activate only if you have at least 7 life more than your starting life total and only as a sorcery.

Alseid of Life's Bounty

Lifelink
{1}, Sacrifice this creature: Target creature or enchantment you control gains protection from the color of your choice until end of turn.

Faith's Fetters

Enchant permanent
When this Aura enters, you gain 4 life.
Enchanted permanent can't attack or block, and its activated abilities can't be activated unless they're mana abilities.