Child of Night

Gloom Sower

Whenever Gloom Sower becomes blocked by a creature, that creature's controller loses 2 life and you gain 2 life.

Nocturnal Feeder

Flying
When Nocturnal Feeder dies, each opponent loses 2 life and you gain 2 life.

Gifted Aetherborn

Blood Host

{1}{B}, Sacrifice another creature: Put a +1/+1 counter on Blood Host and you gain 2 life.

Agonizing Syphon

Agonizing Syphon deals 3 damage to any target and you gain 3 life.

Bloodbond Vampire

Whenever you gain life, put a +1/+1 counter on Bloodbond Vampire.

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.)

Last Gasp

Target creature gets -3/-3 until end of turn.

Silversmote Ghoul

At the beginning of your end step, if you gained 3 or more life this turn, return Silversmote Ghoul from your graveyard to the battlefield tapped.
{1}{B}, Sacrifice Silversmote Ghoul: Draw a card.

Thriving Moor

Thriving Moor enters tapped. As it enters, choose a color other than black.
{T}: Add {B} or one mana of the chosen color.

Sanguine Indulgence

This spell costs {3} less to cast if you've gained 3 or more life this turn.
Return up to two target creature cards from your graveyard to your hand.

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.