Cry of Contrition

Target player discards a card.
Haunt (When this spell card is put into a graveyard after resolving, exile it haunting target creature.)
When the creature this card haunts dies, target player discards a card.

Devour Intellect

Target opponent discards a card. If mana from a Treasure was spent to cast this spell, instead that player reveals their hand, you choose a nonland card from it, then that player discards that card.

Abyssal Nocturnus

Whenever an opponent discards a card, this creature gets +2/+2 and gains fear until end of turn. (It can't be blocked except by artifact creatures and/or black creatures.)

Tourach, Dread Cantor

Kicker {B}{B} (You may pay an additional {B}{B} as you cast this spell.)
Protection from white
Whenever an opponent discards a card, put a +1/+1 counter on Tourach.
When Tourach enters, if it was kicked, target opponent discards two cards at random.

Waste Not

Whenever an opponent discards a creature card, create a 2/2 black Zombie creature token.
Whenever an opponent discards a land card, add {B}{B}.
Whenever an opponent discards a noncreature, nonland card, draw a card.

Fell Specter

Flying
When this creature enters, target opponent discards a card.
Whenever an opponent discards a card, that player loses 2 life.

Sheoldred, the Apocalypse

Deathtouch
Whenever you draw a card, you gain 2 life.
Whenever an opponent draws a card, they lose 2 life.

Liliana's Caress

Whenever an opponent discards a card, that player loses 2 life.

Varragoth, Bloodsky Sire

Deathtouch
Boast — {1}{B}: Target player searches their library for a card, then shuffles and puts that card on top. (Activate only if this creature attacked this turn and only once each turn.)

Temple of the Dead

(Transforms from Aclazotz, Deepest Betrayal.)
{T}: Add {B}.
{2}{B}, {T}: Transform this land. Activate only if a player has one or fewer cards in hand and only as a sorcery.

Aclazotz, Deepest Betrayal

Flying, lifelink
Whenever Aclazotz attacks, each opponent discards a card. For each opponent who can't, you draw a card.
Whenever an opponent discards a land card, create a 1/1 black Bat creature token with flying.
When Aclazotz dies, return it to the battlefield tapped and transformed under its owner's control.

Aclazotz, Deepest Betrayal // Temple of the Dead

Horrifying Revelation

Target player discards a card, then mills a card.

Go for the Throat

Bloodletter of Aclazotz

Flying
If an opponent would lose life during your turn, they lose twice that much life instead. (Damage causes loss of life.)

Megrim

Whenever an opponent discards a card, this enchantment deals 2 damage to that player.

Despise

Target opponent reveals their hand. You choose a creature or planeswalker card from it. That player discards that card.

Underworld Dreams

Whenever an opponent draws a card, this enchantment deals 1 damage to that player.

Ostracize

Target opponent reveals their hand. You choose a creature card from it. That player discards that card.

Raiders' Wake

Whenever an opponent discards a card, that player loses 2 life.
Raid — At the beginning of your end step, if you attacked this turn, target opponent discards a card.

King Macar, the Gold-Cursed

Inspired — Whenever King Macar becomes untapped, you may exile target creature. If you do, create a Gold token. (It's an artifact with "Sacrifice this token: Add one mana of any color.")

Geth's Grimoire

Whenever an opponent discards a card, you may draw a card.

Mind Twist

Target player discards X cards at random.

Locthwain Scorn

Target creature gets -3/-3 until end of turn. You gain 2 life.

Virtue of Persistence

At the beginning of your upkeep, put target creature card from a graveyard onto the battlefield under your control.

Virtue of Persistence // Locthwain Scorn

Sangromancer

Flying
Whenever a creature an opponent controls dies, you may gain 3 life.
Whenever an opponent discards a card, you may gain 3 life.

Harsh Scrutiny

Target opponent reveals their hand. You choose a creature card from it. That player discards that card. Scry 1.