Sanguine Bond

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

Plains

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.)

Unholy Strength

Enchant creature
Enchanted creature gets +2/+1.

Swamp

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.)

Crypt Incursion

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

Sungrace Pegasus

Flying (This creature can't be blocked except by creatures with flying or reach.)
Lifelink (Damage dealt by this creature also causes you to gain that much life.)

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.

Cathedral Sanctifier

When Cathedral Sanctifier enters the battlefield, you gain 3 life.

Dogged Pursuit

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

Pacifism

Enchant creature
Enchanted creature can't attack or block.

Sign in Blood

Target player draws two cards and loses 2 life.

Daggerdrome Imp

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

Exquisite Blood

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

Child of Night

Pulse Tracker

Whenever Pulse Tracker attacks, each opponent loses 1 life.

Defiant Bloodlord

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

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.

Ephara's Radiance

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

Angel's Mercy

Nyx-Fleece Ram

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

Wall of Essence

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

Trained Caracal

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

Soulmender

Ajani's Sunstriker

Zulaport Cutthroat

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

Victim of Night

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

Altar's Reap

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

Divine Favor

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

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.