Have

Unholy Strength

Enchant creature
Enchanted creature gets +2/+1.

Reassembling Skeleton

{1}{B}: Return this card from your graveyard to the battlefield tapped.

Necroduality

Whenever a nontoken Zombie you control enters, create a token that's a copy of that creature.

Putrid Goblin

Persist (When this creature 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.)

Island

Tresserhorn Skyknight

Flying
Prevent all damage that would be dealt to this creature by creatures with first strike.

Nightcreep

Until end of turn, all creatures become black and all lands become Swamps.

Thran Vigil

Whenever one or more artifact and/or creature cards leave your graveyard during your turn, put a +1/+1 counter on target creature you control.

Accursed Horde

{1}{B}: Target attacking Zombie gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it still dies.)

Disciple of Deceit

Inspired — Whenever this creature becomes untapped, you may discard a nonland card. If you do, search your library for a card with the same mana value as that card, reveal it, put it into your hand, then shuffle.

Zombie Outlander

Tendrils of Corruption

Tendrils of Corruption deals X damage to target creature and you gain X life, where X is the number of Swamps you control.

Gravedigger

When this creature enters, you may return target creature card from your graveyard to your hand.

Rise from the Grave

Put target creature card from a graveyard onto the battlefield under your control. That creature is a black Zombie in addition to its other colors and types.

Diregraf Captain

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

Salt Marsh

This land enters tapped.
{T}: Add {U} or {B}.

Festering Goblin

When this creature dies, target creature gets -1/-1 until end of turn.

Woebearer

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Whenever this creature deals combat damage to a player, you may return target creature card from your graveyard to your hand.

Raise Dead

Return target creature card from your graveyard to your hand.

Stitcher's Graft

Equipped creature gets +3/+3.
Whenever equipped creature attacks, it doesn't untap during its controller's next untap step.
Whenever this Equipment becomes unattached from a permanent, sacrifice that permanent.
Equip {2}

Carrion Howler

Pay 1 life: This creature gets +2/-1 until end of turn.

Angrath, Captain of Chaos

Creatures you control have menace.
−2: 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.)

Swamp

Hobbling Zombie

Deathtouch
When this creature dies, create a 2/2 black Zombie creature token with decayed. (It can't block. When it attacks, sacrifice it at end of combat.)

Diregraf Ghoul

Ghoulraiser

When this creature enters, return a Zombie card at random from your graveyard to your hand.

Offer Immortality

Target creature gains deathtouch and indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Tormented Soul

This creature can't block and can't be blocked.

Soured Springs

This land enters tapped.
When this land enters, it deals 1 damage to target opponent.
{T}: Add {U} or {B}.