Horned Cheetah

Whenever Horned Cheetah deals damage, you gain that much life.

Abzan Ascendancy

When Abzan Ascendancy enters the battlefield, put a +1/+1 counter on each creature you control.
Whenever a nontoken creature you control dies, create a 1/1 white Spirit creature token with flying.

Spirit Loop

Enchant creature you control
Whenever enchanted creature deals damage, you gain that much life.
When Spirit Loop is put into a graveyard from the battlefield, return Spirit Loop to its owner's hand.

Spirit Link

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)
Whenever enchanted creature deals damage, you gain that much life.

Paladin of Prahv

Whenever Paladin of Prahv deals damage, you gain that much life.
Forecast — {1}{W}, Reveal Paladin of Prahv from your hand: Whenever target creature deals damage this turn, you gain that much life. (Activate only during your upkeep and only once each turn.)

Necravolver

Kicker {1}{G} and/or {W} (You may pay an additional {1}{G} and/or {W} as you cast this spell.)
If Necravolver was kicked with its {1}{G} kicker, it enters the battlefield with two +1/+1 counters on it and with trample.
If Necravolver was kicked with its {W} kicker, it enters the battlefield with a +1/+1 counter on it and with "Whenever Necravolver deals damage, you gain that much life."

Armadillo Cloak

Enchant creature
Enchanted creature gets +2/+2 and has trample.
Whenever enchanted creature deals damage, you gain that much life.

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.

Winding Constrictor

If one or more counters would be put on an artifact or creature you control, that many plus one of each of those kinds of counters are put on that permanent instead.
If you would get one or more counters, you get that many plus one of each of those kinds of counters instead.

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.

Karlov of the Ghost Council

Whenever you gain life, put two +1/+1 counters on Karlov of the Ghost Council.
{W}{B}, Remove six +1/+1 counters from Karlov of the Ghost Council: Exile target creature.

Soul Link

Enchant creature
Whenever enchanted creature deals damage, you gain that much life.
Whenever enchanted creature is dealt damage, you gain that much life.

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.

Guardian Project

Whenever a nontoken creature enters the battlefield under your control, if it doesn't have the same name as another creature you control or a creature card in your graveyard, draw a card.

Vampiric Link

Enchant creature
Whenever enchanted creature deals damage, you gain that much life.

Soul Warden

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

Indatha Triome

({T}: Add {W}, {B}, or {G}.)
Indatha Triome enters the battlefield tapped.
Cycling {3} ({3}, Discard this card: Draw a card.)

Mourning Thrull

({W/B} can be paid with either {W} or {B}.)
Flying
Whenever Mourning Thrull deals damage, you gain that much life.

Phantom Nishoba

Trample
Phantom Nishoba enters the battlefield with seven +1/+1 counters on it.
Whenever Phantom Nishoba deals damage, you gain that much life.
If damage would be dealt to Phantom Nishoba, prevent that damage. Remove a +1/+1 counter from Phantom Nishoba.

Arcane Signet

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

Zebra Unicorn

Whenever Zebra Unicorn deals damage, you gain that much life.

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.

Essence Warden

Mirari's Wake

Creatures you control get +1/+1.
Whenever you tap a land for mana, add one mana of any type that land produced.

Kambal, Consul of Allocation

Whenever an opponent casts a noncreature spell, that player loses 2 life and you gain 2 life.