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.

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.

Unnerve

Tinybones, Trinket Thief

At the beginning of each end step, if an opponent discarded a card this turn, you draw a card and you lose 1 life.
{4}{B}{B}: Each opponent with no cards in hand loses 10 life.

Bottomless Pit

At the beginning of each player's upkeep, that player discards a card at random.

Plaguecrafter

When this creature enters, each player sacrifices a creature or planeswalker of their choice. Each player who can't discards a card.

Painful Quandary

Whenever an opponent casts a spell, that player loses 5 life unless they discard a card.

Arterial Flow

Each opponent discards two cards. If you control a Vampire, each opponent loses 2 life and you gain 2 life.

Liliana of the Veil

+1: Each player discards a card.
−2: Target player sacrifices a creature.
−6: Separate all permanents target player controls into two piles. That player sacrifices all permanents in the pile of their choice.

Nezumi Informant

When this creature enters, each opponent discards a card.

Burglar Rat

Hypnotic Specter

Flying
Whenever this creature deals damage to an opponent, that player discards a card at random.

Oppression

Whenever a player casts a spell, that player discards a card.

Swamp

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.

Necrogen Mists

At the beginning of each player's upkeep, that player discards a card.

Urgoros, the Empty One

Flying
Whenever Urgoros deals combat damage to a player, that player discards a card at random. If the player can't, you 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.

Creeping Dread

At the beginning of your upkeep, each player discards a card. Each opponent who discarded a card that shares a card type with the card you discarded loses 3 life. (Players reveal the discarded cards simultaneously.)

Shrieking Affliction

At the beginning of each opponent's upkeep, if that player has one or fewer cards in hand, they lose 3 life.

Wheel of Torture

At the beginning of each opponent's upkeep, this artifact deals X damage to that player, where X is 3 minus the number of cards in their hand.

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.

Cunning Lethemancer

At the beginning of your upkeep, each player discards a card.

Tasigur's Cruelty

Delve (Each card you exile from your graveyard while casting this spell pays for {1}.)
Each opponent discards two cards.

Liliana, Defiant Necromancer

+2: Each player discards a card.
−X: Return target nonlegendary creature card with mana value X from your graveyard to the battlefield.
−8: You get an emblem with "Whenever a creature dies, return it to the battlefield under your control at the beginning of the next end step."

Liliana, Heretical Healer

Lifelink
Whenever another nontoken creature you control dies, exile Liliana, Heretical Healer, then return her to the battlefield transformed under her owner's control. If you do, create a 2/2 black Zombie creature token.

Liliana, Heretical Healer // Liliana, Defiant Necromancer

Cruel Grimnarch

Deathtouch
When this creature enters, each opponent discards a card. For each opponent who can't, you gain 4 life.

Liliana's Caress

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

Elderfang Disciple

Mindslicer

When this creature dies, each player discards their hand.

Virus Beetle

Geth's Grimoire

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

Hopeless Nightmare

When this enchantment enters, each opponent discards a card and loses 2 life.
When this enchantment is put into a graveyard from the battlefield, scry 2.
{2}{B}: Sacrifice this enchantment.

Skullslither Worm

When this creature enters, each opponent discards a card. For each opponent who can't, put two +1/+1 counters on this creature.

Liliana's Specter

Flying
When this creature enters, each opponent discards a card.

Miasmic Mummy

When this creature enters, each player discards a card.

Bad Deal

You draw two cards and each opponent discards two cards. Each player loses 2 life.

Vicious Rumors

Vicious Rumors deals 1 damage to each opponent. Each opponent discards a card, then mills a card. You gain 1 life.

Rankle's Prank

Choose one or more —
• Each player discards two cards.
• Each player loses 4 life.
• Each player sacrifices two creatures of their choice.

Dark Deal

Each player discards all the cards in their hand, then draws that many cards minus one.

The Raven Man

At the beginning of each end step, if a player discarded a card this turn, create a 1/1 black Bird creature token with flying and "This token can't block."
{3}{B}, {T}: Each opponent discards a card. Activate only as a sorcery.

Noetic Scales

At the beginning of each player's upkeep, return to its owner's hand each creature that player controls with power greater than the number of cards in their hand.

Necrogoyf

Necrogoyf's power is equal to the number of creature cards in all graveyards.
At the beginning of each player's upkeep, that player discards a card.
Madness {1}{B}{B} (If you discard this card, discard it into exile. When you do, cast it for its madness cost or put it into your graveyard.)

Megrim

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

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Words of Waste

{1}: The next time you would draw a card this turn, each opponent discards a card instead.

Demon's Disciple

When this creature enters, each player sacrifices a creature or planeswalker of their choice.