Defiant Bloodlord

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

Pacifism

Enchant creature
Enchanted creature can't attack or block.

Child of Night

Cathedral Sanctifier

When Cathedral Sanctifier enters, you gain 3 life.

Zulaport Cutthroat

Whenever Zulaport Cutthroat or another creature you control dies, each opponent loses 1 life and you gain 1 life.

Exquisite Blood

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

Soulmender

Ephara's Radiance

Enchant creature
Enchanted creature has "{1}{W}, {T}: You gain 3 life."

Nyx-Fleece Ram

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

Crypt Incursion

Exile all creature cards from target player's graveyard. You gain 3 life for each card exiled this way.

Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Ajani's Sunstriker

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Victim of Night

Destroy target non-Vampire, non-Werewolf, non-Zombie creature.

Pulse Tracker

Whenever this creature attacks, each opponent loses 1 life.

Divine Favor

Enchant creature
When Divine Favor enters, you gain 3 life.
Enchanted creature gets +1/+3.

Spirit Link

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

Sungrace Pegasus

Flying
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Angel's Mercy

Altar's Reap

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Swamp

Daggerdrome Imp

Dogged Pursuit

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

Eternal Thirst

Enchant creature
Enchanted creature has lifelink and "Whenever a creature an opponent controls dies, put a +1/+1 counter on this creature." (Damage dealt by a creature with lifelink also causes its controller to gain that much life.)

Plains

Unholy Strength

Enchant creature
Enchanted creature gets +2/+1.

Basilica Screecher

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.)

Chalice of Death

Chalice of Life

{T}: You gain 1 life. Then if you have at least 10 life more than your starting life total, transform Chalice of Life.

Chalice of Life // Chalice of Death

Wall of Essence

Defender (This creature can't attack.)
Whenever Wall of Essence is dealt combat damage, you gain that much life.