Liliana, Dreadhorde General

Whenever a creature you control dies, draw a card.
+1: Create a 2/2 black Zombie creature token.
−4: Each player sacrifices two creatures of their choice.
−9: Each opponent chooses a permanent they control of each permanent type and sacrifices the rest.

Midnight Snack

Raid — At the beginning of your end step, if you attacked this turn, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
{2}{B}, Sacrifice this enchantment: Target opponent loses X life, where X is the amount of life you gained this turn.

Stab

Target creature gets -2/-2 until end of turn.

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Bloodthirsty Conqueror

Flying, deathtouch
Whenever an opponent loses life, you gain that much life. (Damage causes loss of life.)

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.)

Infestation Sage

When this creature dies, create a 1/1 black and green Insect creature token with flying.

Vengeful Bloodwitch

Whenever this creature or another creature you control dies, target opponent loses 1 life and you gain 1 life.

Swamp

Sanguine Syphoner

Whenever this creature attacks, each opponent loses 1 life and you gain 1 life.

Swiftfoot Boots

Equipped creature has hexproof and haste. (It can't be the target of spells or abilities your opponents control. It can attack and {T} no matter when it came under your control.)
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Exsanguinate

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

Pilfer

Target opponent reveals their hand. You choose a nonland card from it. That player discards that card.