Soul's Attendant

Whenever another creature enters, you may gain 1 life.

Mummy Paramount

Whenever another Zombie you control enters, this creature gets +1/+1 until end of turn.

In Oketra's Name

Zombies you control get +2/+1 until end of turn. Other creatures you control get +1/+1 until end of turn.

Soul Warden

Whenever another creature enters, you gain 1 life.

Guide of Souls

Whenever another creature you control enters, you gain 1 life and get {E} (an energy counter).
Whenever you attack, you may pay {E}{E}{E}. When you do, put two +1/+1 counters and a flying counter on target attacking creature. It becomes an Angel in addition to its other types.

Resolute Strike

Target creature gets +2/+2 until end of turn. If it's a Warrior, you may attach an Equipment you control to it.

Boss's Chauffeur

This creature enters with a number of +1/+1 counters on it equal to one plus the number of other creatures you control.
Alliance — Whenever another creature you control enters, put a +1/+1 counter on this creature.
When this creature dies, create a 1/1 green and white Citizen creature token for each +1/+1 counter on it.

Rush of Battle

Creatures you control get +2/+1 until end of turn. Warrior creatures you control gain lifelink until end of turn. (Damage dealt by those Warriors also causes their controller to gain that much life.)

God-Eternal Oketra

Double strike
Whenever you cast a creature spell, create a 4/4 black Zombie Warrior creature token with vigilance.
When God-Eternal Oketra dies or is put into exile from the battlefield, you may put it into its owner's library third from the top.

Charismatic Conqueror

Vigilance
Whenever an artifact or creature an opponent controls enters untapped, they may tap that permanent. If they don't, you create a 1/1 white Vampire creature token with lifelink.

Obsidian Battle-Axe

Equipped creature gets +2/+1 and has haste.
Whenever a Warrior creature enters, you may attach this Equipment to it.
Equip {3}

Tax Collector

When this creature enters, choose one —
• Tax — Until your next turn, spells your opponents cast cost {1} more to cast.
• Arrest — Detain target creature an opponent controls. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)

Arashin Foremost

Double strike
Whenever this creature enters or attacks, another target Warrior creature you control gains double strike until end of turn.

Mondrak, Glory Dominus

If one or more tokens would be created under your control, twice that many of those tokens are created instead.
{1}{W/P}{W/P}, Sacrifice two other artifacts and/or creatures: Put an indestructible counter on Mondrak. ({W/P} can be paid with either {W} or 2 life.)

Securitron Squadron

Squad {3} (As an additional cost to cast this spell, you may pay {3} any number of times. When this creature enters, create that many tokens that are copies of it.)
Vigilance
Whenever a creature token you control enters, put a +1/+1 counter on it.

Binding Mummy

Whenever another Zombie you control enters, you may tap target artifact or creature.

Whitemane Lion

Flash
When this creature enters, return a creature you control to its owner's hand.

Anointer Priest

Whenever a creature token you control enters, you gain 1 life.
Embalm {3}{W} ({3}{W}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a white Zombie Human Cleric with no mana cost. Embalm only as a sorcery.)

Mardu Woe-Reaper

Whenever this creature or another Warrior you control enters, you may exile target creature card from a graveyard. If you do, you gain 1 life.

Time to Reflect

Exile target creature that blocked or was blocked by a Zombie this turn.

Cathars' Crusade

Whenever a creature you control enters, put a +1/+1 counter on each creature you control.

Suture Priest

Whenever another creature you control enters, you may gain 1 life.
Whenever a creature an opponent controls enters, you may have that player lose 1 life.

Unconventional Tactics

Target creature gets +3/+3 and gains flying until end of turn.
Whenever a Zombie you control enters, you may pay {W}. If you do, return this card from your graveyard to your hand.