Cemetery Desecrator

Menace
When this creature enters or dies, exile another card from a graveyard. When you do, choose one —
• Remove X counters from target permanent, where X is the mana value of the exiled card.
• Target creature an opponent controls gets -X/-X until end of turn, where X is the mana value of the exiled card.

Marchesa, the Black Rose

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Other creatures you control have dethrone.
Whenever a creature you control with a +1/+1 counter on it dies, return that card to the battlefield under your control at the beginning of the next end step.

Behemoth of Vault 0

Trample
When this creature enters, you get {E}{E}{E}{E} (four energy counters).
When this creature dies, you may pay an amount of {E} equal to target nonland permanent's mana value. When you do, destroy that permanent.

Chaos Defiler

Trample
Battle Cannon — When this creature enters or dies, for each opponent, choose a nonland permanent that player controls. Destroy one of them chosen at random.

Shadow the Hedgehog

Haste
Whenever Shadow the Hedgehog or another creature you control with flash or haste dies, draw a card.
Chaos Control — Each spell you cast has split second if mana from an artifact was spent to cast it. (As long as it's on the stack, players can't cast spells or activate abilities that aren't mana abilities.)

Bone Devourer

Flash
Flying
This creature enters with a number of +1/+1 counters on it equal to the number of creatures that died this turn.
When this creature dies, you draw X cards and you lose X life, where X is the number of +1/+1 counters on it.

Clone Shell

Imprint — When this creature enters, look at the top four cards of your library, exile one face down, then put the rest on the bottom of your library in any order.
When this creature dies, turn the exiled card face up. If it's a creature card, put it onto the battlefield under your control.

Cavalier of Night

Lifelink
When this creature enters, you may sacrifice another creature. When you do, destroy target creature an opponent controls.
When this creature dies, return target creature card with mana value 3 or less from your graveyard to the battlefield.

Demon of Dark Schemes

Flying
When this creature enters, all other creatures get -2/-2 until end of turn.
Whenever another creature dies, you get {E} (an energy counter).
{2}{B}, Pay {E}{E}{E}{E}: Put target creature card from a graveyard onto the battlefield under your control tapped.

Cyclops Superconductor

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, you get {E}{E}{E} (three energy counters).
When this creature dies, you may pay {E}{E}{E}. When you do, this creature deals damage equal to its power to any target.

Cynette, Jelly Drover

When Cynette enters or dies, create a 1/1 blue Jellyfish creature token with flying.
Creatures you control with flying get +1/+1.