Light of Promise

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

Path of Bravery

As long as your life total is greater than or equal to your starting life total, creatures you control get +1/+1.
Whenever one or more creatures you control attack, you gain life equal to the number of attacking creatures.

Angelic Chorus

Whenever a creature you control enters, you gain life equal to its toughness.

Archon of Redemption

Flying
Whenever this creature or another creature you control with flying enters, you may gain life equal to that creature's power.

Boon Reflection

If you would gain life, you gain twice that much life instead.

Gideon's Company

Whenever you gain life, put two +1/+1 counters on this creature.
{3}{W}: Put a loyalty counter on target Gideon planeswalker.

Serene Steward

Whenever you gain life, you may pay {W}. If you do, put a +1/+1 counter on target creature.

Atalya, Samite Master

{X}, {T}: Choose one —
• Prevent the next X damage that would be dealt to target creature this turn. Spend only white mana on X.
• You gain X life. Spend only white mana on X.

Renewed Faith

You gain 6 life.
Cycling {1}{W} ({1}{W}, Discard this card: Draw a card.)
When you cycle this card, you may gain 2 life.

Children of Korlis

Sacrifice this creature: You gain life equal to the life you've lost this turn. (Damage causes loss of life.)

Ajani's Pridemate

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

Angel of Vitality

Flying
If you would gain life, you gain that much life plus 1 instead.
This creature gets +2/+2 as long as you have 25 or more life.

Sunbond

Famished Paladin

This creature doesn't untap during your untap step.
Whenever you gain life, untap this creature.

Cradle of Vitality

Whenever you gain life, you may pay {1}{W}. If you do, put a +1/+1 counter on target creature for each 1 life you gained.

Revitalize

Attended Healer

Whenever you gain life for the first time each turn, create a 1/1 white Cat creature token.
{2}{W}: Another target Cleric gains lifelink until end of turn.

Rhox Faithmender

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
If you would gain life, you gain twice that much life instead.