Undying Malice

Until end of turn, target creature gains "When this creature dies, return it to the battlefield tapped under its owner's control with a +1/+1 counter on it."

Shambling Ghast

When Shambling Ghast dies, choose one —
• Target creature an opponent controls gets -1/-1 until end of turn.
• Create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Haunt of the Dead Marshes

When Haunt of the Dead Marshes enters, scry 1.
{2}{B}: Return Haunt of the Dead Marshes from your graveyard to the battlefield tapped. Activate only if you control a legendary creature.

Qarsi Sadist

Exploit (When this creature enters, you may sacrifice a creature.)
When Qarsi Sadist exploits a creature, target opponent loses 2 life and you gain 2 life.

Ichor Drinker

Lifelink
{B}, Exile Ichor Drinker from your graveyard: Incubate 2. Activate only as a sorcery. (Create an Incubator token with two +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Nested Shambler

When Nested Shambler dies, create X tapped 1/1 green Squirrel creature tokens, where X is Nested Shambler's power.

Ashen-Skin Zubera

When Ashen-Skin Zubera dies, target opponent discards a card for each Zubera that died this turn.

Feign Death

Augur of Skulls

{1}{B}: Regenerate Augur of Skulls.
Sacrifice Augur of Skulls: Target player discards two cards. Activate only during your upkeep.

Mindleech Ghoul

Exploit (When this creature enters, you may sacrifice a creature.)
When Mindleech Ghoul exploits a creature, each opponent exiles a card from their hand.