K'rrik, Son of Yawgmoth

({B/P} can be paid with either {B} or 2 life.)
Lifelink
For each {B} in a cost, you may pay 2 life rather than pay that mana.
Whenever you cast a black spell, put a +1/+1 counter on K'rrik, Son of Yawgmoth.

Lotus Petal

{T}, Sacrifice Lotus Petal: Add one mana of any color.

Vampire Nighthawk

Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)
Lifelink (Damage dealt by this creature also causes you to 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.

Exsanguinate

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

Dark Ritual

Nip Gwyllion

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

Healer's Hawk

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

Ishai, Ojutai Dragonspeaker

Flying
Whenever an opponent casts a spell, put a +1/+1 counter on Ishai, Ojutai Dragonspeaker.
Partner (You can have two commanders if both have partner.)

Sign in Blood

Target player draws two cards and loses 2 life.

Divinity of Pride

Flying, lifelink
Divinity of Pride gets +4/+4 as long as you have 25 or more 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.