Angelic Accord

At the beginning of each end step, if you gained 4 or more life this turn, create a 4/4 white Angel creature token with flying.

Voice of the Blessed

Whenever you gain life, put a +1/+1 counter on Voice of the Blessed.
As long as Voice of the Blessed has four or more +1/+1 counters on it, it has flying and vigilance.
As long as Voice of the Blessed has ten or more +1/+1 counters on it, it has indestructible.

Heliod, Sun-Crowned

Indestructible
As long as your devotion to white is less than five, Heliod isn't a creature.
Whenever you gain life, put a +1/+1 counter on target creature or enchantment you control.
{1}{W}: Another target creature gains lifelink until end of turn.

Boon Reflection

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

Nyx-Fleece Ram

At the beginning of your upkeep, you gain 1 life.

Awe Strike

The next time target creature would deal damage this turn, prevent that damage. You gain life equal to the damage prevented this way.

Union of the Third Path

Draw a card, then you gain life equal to the number of cards in your hand.

Chastise

Destroy target attacking creature. You gain life equal to its power.

Soul's Grace

You gain life equal to target creature's power.

Proper Burial

Whenever a creature you control dies, you gain life equal to that creature's toughness.

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.

Plains

Archon of Redemption

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

Soulmender

Archangel of Thune

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Whenever you gain life, put a +1/+1 counter on each creature you control.

Riot Control

You gain 1 life for each creature your opponents control. Prevent all damage that would be dealt to you this 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.

Kabira Crossroads

Kabira Crossroads enters tapped.
When Kabira Crossroads enters, you gain 2 life.
{T}: Add {W}.

Nykthos Paragon

Whenever you gain life, you may put that many +1/+1 counters on each creature you control. Do this only once each turn.

Plea for Guidance

Search your library for up to two enchantment cards, reveal them, put them into your hand, then shuffle.

Well of Lost Dreams

Whenever you gain life, you may pay {X}, where X is less than or equal to the amount of life you gained. If you do, draw X cards.

Lagonna-Band Storyteller

When Lagonna-Band Storyteller enters, you may put target enchantment card from your graveyard on top of your library. If you do, you gain life equal to its mana value.

Honor's Reward

You gain 4 life. Bolster 2. (Choose a creature with the least toughness among creatures you control and put two +1/+1 counters on it.)