Heron of Hope

Flying
If you would gain life, you gain that much life plus 1 instead.
{1}{W}: Heron of Hope gains lifelink until end of turn.

Orim's Prayer

Whenever one or more creatures attack you, you gain 1 life for each attacking creature.

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.

Elenda's Hierophant

Flying
Whenever you gain life, put a +1/+1 counter on Elenda's Hierophant.
When Elenda's Hierophant dies, create X 1/1 white Vampire creature tokens with lifelink, where X is its power.

Ancient Tomb

{T}: Add {C}{C}. Ancient Tomb deals 2 damage to you.

Gerrard Capashen

At the beginning of your upkeep, you gain 1 life for each card in target opponent's hand.
{3}{W}: Tap target creature. Activate only if Gerrard Capashen is attacking.

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.

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.

Children of Korlis

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

Reliquary Tower

You have no maximum hand size.
{T}: Add {C}.

Curse of Vitality

Enchant player
Whenever enchanted player is attacked, you gain 2 life. Each opponent attacking that player does the same.

Crested Sunmare

Other Horses you control have indestructible.
At the beginning of each end step, if you gained life this turn, create a 5/5 white Horse creature token.

Purity

Flying
If noncombat damage would be dealt to you, prevent that damage. You gain life equal to the damage prevented this way.
When Purity is put into a graveyard from anywhere, shuffle it into its owner's library.

Archivist of Oghma

Flash
Whenever an opponent searches their library, you gain 1 life and draw a card.

Blighted Steppe

{T}: Add {C}.
{3}{W}, {T}, Sacrifice Blighted Steppe: You gain 2 life for each creature you control.

Firemane Commando

Flying
Whenever you attack with two or more creatures, draw a card.
Whenever another player attacks with two or more creatures, they draw a card if none of those creatures attacked you.

Sunscorch Regent

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Sunscorch Regent and you gain 1 life.

Resplendent Angel

Flying
At the beginning of each end step, if you gained 5 or more life this turn, create a 4/4 white Angel creature token with flying and vigilance.
{3}{W}{W}{W}: Until end of turn, Resplendent Angel gets +2/+2 and gains lifelink.

Plains

Hallow

Prevent all damage target spell would deal this turn. You gain life equal to the damage prevented this way.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Wall of Reverence

Defender, flying
At the beginning of your end step, you may gain life equal to the power of target creature you control.

Sun Droplet

Whenever you're dealt damage, put that many charge counters on Sun Droplet.
At the beginning of each upkeep, you may remove a charge counter from Sun Droplet. If you do, you gain 1 life.

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.

Moonlit Wake

Whenever a creature dies, you gain 1 life.

Dragon's Claw

Whenever a player casts a red spell, you may gain 1 life.

The One Ring

Indestructible
When The One Ring enters the battlefield, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Profane Memento

Whenever a creature card is put into an opponent's graveyard from anywhere, you gain 1 life.

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.

Auriok Champion

Protection from black and from red
Whenever another creature enters the battlefield, you may gain 1 life.

Sigarda's Splendor

As Sigarda's Splendor enters the battlefield, note your life total.
At the beginning of your upkeep, draw a card if your life total is greater than or equal to the last noted life total for Sigarda's Splendor. Then note your life total.
Whenever you cast a white spell, you gain 1 life.

Demon's Horn

Whenever a player casts a black spell, you may gain 1 life.

Astrid Peth

Whenever Astrid Peth enters the battlefield or attacks, create a Food token.
Brand-new Sky — Whenever you sacrifice a Clue or Food, Astrid Peth explores. (Reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this creature, then put the card back or put it into your graveyard.)

Soul's Attendant

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

Reverse Damage

The next time a source of your choice would deal damage to you this turn, prevent that damage. You gain life equal to the damage prevented this way.

Shattered Angel

Flying
Whenever a land enters the battlefield under an opponent's control, you may gain 3 life.

Resplendent Mentor

White creatures you control have "{T}: You gain 1 life."

Battle Angels of Tyr

Flying, myriad
Whenever Battle Angels of Tyr deals combat damage to a player, draw a card if that player has more cards in hand than each other player. Then you create a Treasure token if that player controls more lands than each other player. Then you gain 3 life if that player has more life than each other player.

Gwaihir, Greatest of the Eagles

Flying
Whenever Gwaihir attacks, target attacking creature gains flying until end of turn.
At the beginning of each end step, if you gained 3 or more life this turn, create a 3/3 white Bird creature token with flying and "Whenever this creature attacks, target attacking creature gains flying until end of turn."

Sierra, Nuka's Biggest Fan

The Nuka-Cola Challenge — Whenever one or more creatures you control deal combat damage to a player, put a quest counter on Sierra, Nuka's Biggest Fan and create a Food token.
Whenever you sacrifice a Food, target creature you control gets +X/+X until end of turn, where X is the number of quest counters on Sierra.

Apothecary White

Vigilance
Whenever you attack, you create a Food token for each player being attacked. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
{W}, {T}, Tap X untapped Foods you control: Create X 1/1 white Human creature tokens.

Colossal Plow

Whenever Colossal Plow attacks, add {W}{W}{W} and you gain 3 life. Until end of turn, you don't lose this mana as steps and phases end.
Crew 6 (Tap any number of creatures you control with total power 6 or more: This Vehicle becomes an artifact creature until end of turn.)

Contemplation

Whenever you cast a spell, you gain 1 life.

Celestial Force

At the beginning of each upkeep, you gain 3 life.

Twinblade Paladin

Whenever you gain life, put a +1/+1 counter on Twinblade Paladin.
As long as you have 25 or more life, Twinblade Paladin has double strike. (It deals both first-strike and regular combat damage.)

The Gaffer

At the beginning of each end step, if you gained 3 or more life this turn, draw a card.

Trouble in Pairs

If an opponent would begin an extra turn, that player skips that turn instead.
Whenever an opponent attacks you with two or more creatures, draws their second card each turn, or casts their second spell each turn, you draw a card.

Silverstrike

Destroy target attacking creature. You gain 3 life.

Kraken's Eye

Whenever a player casts a blue spell, you may gain 1 life.

Cleric Class

(Gain the next level as a sorcery to add its ability.)
If you would gain life, you gain that much life plus 1 instead.
{3}{W}: Level 2
Whenever you gain life, put a +1/+1 counter on target creature you control.
{4}{W}: Level 3
When this Class becomes level 3, return target creature card from your graveyard to the battlefield. You gain life equal to that creature's toughness.

Angel's Feather

Whenever a player casts a white spell, you may gain 1 life.

Venser's Journal

You have no maximum hand size.
At the beginning of your upkeep, you gain 1 life for each card in your hand.

Terashi's Grasp

Destroy target artifact or enchantment. You gain life equal to its mana value.

Radiant Fountain

When Radiant Fountain enters the battlefield, you gain 2 life.
{T}: Add {C}.

Righteous Cause

Whenever a creature attacks, you gain 1 life.

Generous Gift

Destroy target permanent. Its controller creates a 3/3 green Elephant creature token.

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.

Knight of Dawn's Light

First strike
If you would gain life, you gain that much life plus 1 instead.
{1}{W}: Knight of Dawn's Light gets +1/+1 until end of turn.

Wurm's Tooth

Whenever a player casts a green spell, you may gain 1 life.

Nuka-Cola Vending Machine

{1}, {T}: Create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")
Whenever you sacrifice a Food, create a tapped Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Miren, the Moaning Well

{T}: Add {C}.
{3}, {T}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Soul Warden

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

Chastise

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

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Angel of Vitality

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

Sol Ring

Triumphant Surge

Destroy target creature with power 4 or greater. You gain 3 life.

Ashes of the Abhorrent

Players can't cast spells from graveyards or activate abilities of cards in graveyards.
Whenever a creature dies, you gain 1 life.

Smuggler's Share

At the beginning of each end step, draw a card for each opponent who drew two or more cards this turn, then create a Treasure token for each opponent who had two or more lands enter the battlefield under their control this turn.

Authority of the Consuls

Creatures your opponents control enter the battlefield tapped.
Whenever a creature enters the battlefield under an opponent's control, you gain 1 life.