Eternal Skylord

When Eternal Skylord enters, amass Zombies 2. (Put two +1/+1 counters on an Army you control. It's also a Zombie. If you don't control an Army, create a 0/0 black Zombie Army creature token first.)
Zombie tokens you control have flying.

Gavony Unhallowed

Whenever another creature you control dies, put a +1/+1 counter on Gavony Unhallowed.

Necromancer's Covenant

When Necromancer's Covenant enters, exile all creature cards from target player's graveyard, then create a 2/2 black Zombie creature token for each card exiled this way.
Zombies you control have lifelink.

Grave Pact

Whenever a creature you control dies, each other player sacrifices a creature.

Tyrant's Choice

Will of the council — Starting with you, each player votes for death or torture. If death gets more votes, each opponent sacrifices a creature. If torture gets more votes or the vote is tied, each opponent loses 4 life.

Gray Merchant of Asphodel

When Gray Merchant of Asphodel enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)

Endless Ranks of the Dead

At the beginning of your upkeep, create X 2/2 black Zombie creature tokens, where X is half the number of Zombies you control, rounded down.

Treacherous Urge

Target opponent reveals their hand. You may put a creature card from it onto the battlefield under your control. That creature gains haste. Sacrifice it at the beginning of the next end step.

Tormod, the Desecrator

Whenever one or more cards leave your graveyard, create a tapped 2/2 black Zombie creature token.
Partner (You can have two commanders if both have partner.)

Nevinyrral, Urborg Tyrant

Hexproof from artifacts, creatures, and enchantments
When Nevinyrral, Urborg Tyrant enters, create a tapped 2/2 black Zombie creature token for each creature that died this turn.
When Nevinyrral dies, you may pay {1}. When you do, destroy all artifacts, creatures, and enchantments.

Liliana's Mastery

Zombies you control get +1/+1.
When Liliana's Mastery enters, create two 2/2 black Zombie creature tokens.

Cemetery Reaper

Other Zombie creatures you control get +1/+1.
{2}{B}, {T}: Exile target creature card from a graveyard. Create a 2/2 black Zombie creature token.

Rottenheart Ghoul

When Rottenheart Ghoul dies, target player discards a card.

Baloth Null

When Baloth Null enters, return up to two target creature cards from your graveyard to your hand.

Relentless Dead

Menace (This creature can't be blocked except by two or more creatures.)
When Relentless Dead dies, you may pay {B}. If you do, return it to its owner's hand.
When Relentless Dead dies, you may pay {X}. If you do, return another target Zombie creature card with mana value X from your graveyard to the battlefield.

Dreg Mangler

Haste
Scavenge {3}{B}{G} ({3}{B}{G}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Liliana's Reaver

Deathtouch
Whenever Liliana's Reaver deals combat damage to a player, that player discards a card and you create a tapped 2/2 black Zombie creature token.

Sewn-Eye Drake

Dread Wanderer

Dread Wanderer enters tapped.
{2}{B}: Return Dread Wanderer from your graveyard to the battlefield. Activate only as a sorcery and only if you have one or fewer cards in hand.

Noxious Ghoul

Whenever Noxious Ghoul or another Zombie enters, all non-Zombie creatures get -1/-1 until end of turn.

Moan of the Unhallowed

Create two 2/2 black Zombie creature tokens.
Flashback {5}{B}{B} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Thraximundar

Haste
Whenever Thraximundar attacks, defending player sacrifices a creature.
Whenever a player sacrifices a creature, you may put a +1/+1 counter on Thraximundar.

Mikaeus, the Unhallowed

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
Whenever a Human deals damage to you, destroy it.
Other non-Human creatures you control get +1/+1 and have undying. (When a creature with undying dies, if it had no +1/+1 counters on it, return it to the battlefield under its owner's control with a +1/+1 counter on it.)

Unraveling Mummy

{1}{W}: Target attacking Zombie gains lifelink until end of turn.
{1}{B}: Target attacking Zombie gains deathtouch until end of turn.

Unscythe, Killer of Kings

Equipped creature gets +3/+3 and has first strike.
Whenever a creature dealt damage by equipped creature this turn dies, you may exile that card. If you do, create a 2/2 black Zombie creature token.
Equip {2}

Infectious Horror

Whenever Infectious Horror attacks, each opponent loses 2 life.

Diregraf Captain

Deathtouch
Other Zombie creatures you control get +1/+1.
Whenever another Zombie you control dies, target opponent loses 1 life.