Children of Korlis

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

Plains

Agent of Masks

At the beginning of your upkeep, each opponent loses 1 life. You gain life equal to the life lost this way.

Murder

Scoured Barrens

This land enters tapped.
When this land enters, you gain 1 life.
{T}: Add {W} or {B}.

Traveler's Amulet

{1}, Sacrifice Traveler's Amulet: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.

Indulging Patrician

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
At the beginning of your end step, if you gained 3 or more life this turn, each opponent loses 3 life.

Approach of the Second Sun

If this spell was cast from your hand and you've cast another spell named Approach of the Second Sun this game, you win the game. Otherwise, put Approach of the Second Sun into its owner's library seventh from the top and you gain 7 life.

Chaplain's Blessing

Pontiff of Blight

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Other creatures you control have extort. (If a creature has multiple instances of extort, each triggers separately.)

Sanguine Bond

Whenever you gain life, target opponent loses that much life.

Witch's Oven

{T}, Sacrifice a creature: Create a Food token. If the sacrificed creature's toughness was 4 or greater, create two Food tokens instead. (They're artifacts with "{2}, {T}, Sacrifice this artifact: You gain 3 life.")

Ill-Gotten Inheritance

At the beginning of your upkeep, Ill-Gotten Inheritance deals 1 damage to each opponent and you gain 1 life.
{5}{B}, Sacrifice Ill-Gotten Inheritance: It deals 4 damage to target opponent and you gain 4 life.

Teysa, Envoy of Ghosts

Vigilance, protection from creatures
Whenever a creature deals combat damage to you, destroy that creature. Create a 1/1 white and black Spirit creature token with flying.

Scion of the Swarm

Flying
Whenever you gain life, put a +1/+1 counter on Scion of the Swarm.

Disciple of Griselbrand

{1}, Sacrifice a creature: You gain life equal to the sacrificed creature's toughness.

Silverquill Campus

Silverquill Campus enters tapped.
{T}: Add {W} or {B}.
{4}, {T}: Scry 1.

Treasury Thrull

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Whenever Treasury Thrull attacks, you may return target artifact, creature, or enchantment card from your graveyard to your hand.

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.

Cruel Celebrant

Whenever Cruel Celebrant or another creature or planeswalker you control dies, each opponent loses 1 life and you gain 1 life.

Orzhov Keyrune

{T}: Add {W} or {B}.
{W}{B}: Orzhov Keyrune becomes a 1/4 white and black Thrull artifact creature with lifelink until end of turn.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Campaign of Vengeance

Whenever a creature you control attacks, defending player loses 1 life and you gain 1 life.

Soul Warden

Whenever another creature enters, you gain 1 life.

Obzedat's Aid

Return target permanent card from your graveyard to the battlefield.

Gift of Orzhova

Enchant creature
Enchanted creature gets +1/+1 and has flying and lifelink.

Orzhov Cluestone

{T}: Add {W} or {B}.
{W}{B}, {T}, Sacrifice Orzhov Cluestone: Draw a card.

Dogged Pursuit

At the beginning of your end step, each opponent loses 1 life and you gain 1 life.

Revenge of Ravens

Whenever a creature attacks you or a planeswalker you control, that creature's controller loses 1 life and you gain 1 life.

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.

Felidar Sovereign

Vigilance (Attacking doesn't cause this creature to tap.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)
At the beginning of your upkeep, if you have 40 or more life, you win the game.

Riot Control

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

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Regal Bloodlord

Flying
At the beginning of each end step, if you gained life this turn, create a 1/1 black Bat creature token with flying.

Bloodthirsty Aerialist

Flying
Whenever you gain life, put a +1/+1 counter on Bloodthirsty Aerialist.

Sign in Blood

Target player draws two cards and loses 2 life.

Despark

Exile target permanent with mana value 4 or greater.

Burnished Hart

{3}, Sacrifice this creature: Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Swamp

Ajani's Pridemate

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

Soulmender

Orzhov Guildgate

This land enters tapped.
{T}: Add {W} or {B}.

Mortify

Epicure of Blood

Talisman of Hierarchy

{T}: Add {C}.
{T}: Add {W} or {B}. Talisman of Hierarchy deals 1 damage to you.

Intangible Virtue

Creature tokens you control get +1/+1 and have vigilance.

Blood Tithe

Each opponent loses 3 life. You gain life equal to the life lost this way.

Defiant Bloodlord

Flying
Whenever you gain life, target opponent loses that much life.

Orzhov Signet

Read the Bones

Scry 2, then draw two cards. You lose 2 life. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Ethereal Absolution

Creatures you control get +1/+1.
Creatures your opponents control get -1/-1.
{2}{W}{B}: Exile target card from an opponent's graveyard. If it was a creature card, you create a 1/1 white and black Spirit creature token with flying.

Kingpin's Pet

Flying
Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Doom Blade

Disenchant

Basilica Screecher

Bladebrand

Target creature gains deathtouch until end of turn.
Draw a card.

Commander's Sphere

{T}: Add one mana of any color in your commander's color identity.
Sacrifice Commander's Sphere: Draw a card.

Arvad the Cursed

Deathtouch, lifelink
Other legendary creatures you control get +2/+2.

Debt to the Deathless

Each opponent loses two times X life. You gain life equal to the life lost this way.

Cliffhaven Vampire

Flying
Whenever you gain life, each opponent loses 1 life.

Congregate

Target player gains 2 life for each creature on the battlefield.

Evolving Wilds

{T}, Sacrifice this land: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Goldmire Bridge

Goldmire Bridge enters tapped.
Indestructible
{T}: Add {W} or {B}.

Sanguine Sacrament

You gain twice X life. Put Sanguine Sacrament on the bottom of its owner's library.

Orzhov Locket

{T}: Add {W} or {B}.
{W/B}{W/B}{W/B}{W/B}, {T}, Sacrifice Orzhov Locket: Draw two cards.

Tithe Drinker

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)

Night Market Lookout

Whenever Night Market Lookout becomes tapped, each opponent loses 1 life and you gain 1 life.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Forsaken Sanctuary

Forsaken Sanctuary enters tapped.
{T}: Add {W} or {B}.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Orzhov Basilica

Orzhov Basilica enters tapped.
When Orzhov Basilica enters, return a land you control to its owner's hand.
{T}: Add {W}{B}.

Drana's Emissary

Flying
At the beginning of your upkeep, each opponent loses 1 life and you gain 1 life.

Tormented Hero

Tormented Hero enters tapped.
Heroic — Whenever you cast a spell that targets Tormented Hero, each opponent loses 1 life. You gain life equal to the life lost this way.

Vizkopa Guildmage

{1}{W}{B}: Target creature gains lifelink until end of turn.
{1}{W}{B}: Whenever you gain life this turn, each opponent loses that much life.