Gravecrawler

Gravecrawler can't block.
You may cast Gravecrawler from your graveyard as long as you control a Zombie.

Champion of the Perished

Whenever another Zombie you control enters, put a +1/+1 counter on Champion of the Perished.

Carrion Feeder

Carrion Feeder can't block.
Sacrifice a creature: Put a +1/+1 counter on Carrion Feeder.

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.

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.)

Undead Augur

Whenever Undead Augur or another Zombie you control dies, you draw a card and you lose 1 life.

Swamp

Viscera Seer

Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Fatal Push

Destroy target creature if it has mana value 2 or less.
Revolt — Destroy that creature if it has mana value 4 or less instead if a permanent you controlled left the battlefield this turn.

Nantuko Husk

Sacrifice a creature: Nantuko Husk gets +2/+2 until end of turn.