Nekusar, the Mindrazer

At the beginning of each player's draw step, that player draws an additional card.
Whenever an opponent draws a card, Nekusar, the Mindrazer deals 1 damage to that player.

Dimir Signet

Liliana's Caress

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

Megrim

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

Perplex

Counter target spell unless its controller discards their hand.
Transmute {1}{U}{B} ({1}{U}{B}, Discard this card: Search your library for a card with the same mana value as this card, reveal it, put it into your hand, then shuffle. Transmute only as a sorcery.)

Blizzard Specter

Flying
Whenever Blizzard Specter deals combat damage to a player, choose one —
• That player returns a permanent they control to its owner's hand.
• That player discards a card.

Guul Draz Specter

Flying
Guul Draz Specter gets +3/+3 as long as an opponent has no cards in hand.
Whenever Guul Draz Specter deals combat damage to a player, that player discards a card.

Hypnotic Specter

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

Blazing Specter

Flying, haste
Whenever Blazing Specter deals combat damage to a player, that player discards a card.

Geth's Grimoire

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

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.

Fate Unraveler

Whenever an opponent draws a card, Fate Unraveler deals 1 damage to that player.

Nightveil Specter

Flying
Whenever Nightveil Specter deals combat damage to a player, that player exiles the top card of their library.
You may play lands and cast spells from among cards exiled with Nightveil Specter.

Painful Quandary

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

Lavaborn Muse

At the beginning of each opponent's upkeep, if that player has two or fewer cards in hand, Lavaborn Muse deals 3 damage to that player.

Waterfront Bouncer

{U}, {T}, Discard a card: Return target creature to its owner's hand.

Sedraxis Specter

Flying
Whenever Sedraxis Specter deals combat damage to a player, that player discards a card.
Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Jace's Phantasm

Flying
Jace's Phantasm gets +4/+4 as long as an opponent has ten or more cards in their graveyard.

Recoil

Return target permanent to its owner's hand. Then that player discards a card.

Altar of the Brood

Whenever another permanent you control enters, each opponent mills a card.

Howling Mine

At the beginning of each player's draw step, if Howling Mine is untapped, that player draws an additional card.

Mindcrank

Whenever an opponent loses life, that player mills that many cards. (Damage causes loss of life.)

The Rack

As The Rack enters, choose an opponent.
At the beginning of the chosen player's upkeep, The Rack deals X damage to that player, where X is 3 minus the number of cards in their hand.

Crucible of Worlds

Library of Leng

You have no maximum hand size.
If an effect causes you to discard a card, discard it, but you may put it on top of your library instead of into your graveyard.

Shrieking Affliction

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

Quest for the Nihil Stone

Whenever an opponent discards a card, you may put a quest counter on Quest for the Nihil Stone.
At the beginning of each opponent's upkeep, if that player has no cards in hand and Quest for the Nihil Stone has two or more quest counters on it, you may have that player lose 5 life.

Pain Magnification

Whenever an opponent is dealt 3 or more damage by a single source, that player discards a card.

Larceny

Whenever a creature you control deals combat damage to a player, that player discards a card.

Underworld Dreams

Whenever an opponent draws a card, Underworld Dreams deals 1 damage to that player.

Curiosity

Enchant creature
Whenever enchanted creature deals damage to an opponent, you may draw a card.

Bloodchief Ascension

At the beginning of each end step, if an opponent lost 2 or more life this turn, you may put a quest counter on Bloodchief Ascension. (Damage causes loss of life.)
Whenever a card is put into an opponent's graveyard from anywhere, if Bloodchief Ascension has three or more quest counters on it, you may have that player lose 2 life. If you do, you gain 2 life.

Fevered Visions

At the beginning of each player's end step, that player draws a card. If the player is your opponent and has four or more cards in hand, Fevered Visions deals 2 damage to that player.

Phyrexian Tyranny

Whenever a player draws a card, that player loses 2 life unless they pay {2}.

Master of the Feast

Flying
At the beginning of your upkeep, each opponent draws a card.

Seizan, Perverter of Truth

At the beginning of each player's upkeep, that player loses 2 life and draws two cards.

Demonic Consultation

Choose a card name. Exile the top six cards of your library, then reveal cards from the top of your library until you reveal a card with the chosen name. Put that card into your hand and exile all other cards revealed this way.

Dictate of Kruphix

Flash
At the beginning of each player's draw step, that player draws an additional card.

Stormfist Crusader

Menace
At the beginning of your upkeep, each player draws a card and loses 1 life.

Thassa's Oracle

When Thassa's Oracle enters, look at the top X cards of your library, where X is your devotion to blue. Put up to one of them on top of your library and the rest on the bottom of your library in a random order. If X is greater than or equal to the number of cards in your library, you win the game. (Each {U} in the mana costs of permanents you control counts toward your devotion to blue.)

Kami of the Crescent Moon

At the beginning of each player's draw step, that player draws an additional card.

Ruby Medallion

Red spells you cast cost {1} less to cast.

Sapphire Medallion

Blue spells you cast cost {1} less to cast.

Jet Medallion

Black spells you cast cost {1} less to cast.

Rakdos Signet

Izzet Signet

Arcane Signet

{T}: Add one mana of any color in your commander's color identity.

Black Vise

As Black Vise enters, choose an opponent.
At the beginning of the chosen player's upkeep, Black Vise deals X damage to that player, where X is the number of cards in their hand minus 4.

Irencrag Pyromancer

Whenever you draw your second card each turn, Irencrag Pyromancer deals 3 damage to any target.

Spellbook

Memory Erosion

Whenever an opponent casts a spell, that player mills two cards.

Jace's Erasure

Whenever you draw a card, you may have target player mill a card.

Sphinx's Tutelage

Whenever you draw a card, target opponent mills two cards. If two nonland cards that share a color were milled this way, repeat this process.
{5}{U}: Draw a card, then discard a card.

Dreadbore

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Dream Fracture

Counter target spell. Its controller draws a card.
Draw a card.

Browbeat

Any player may have Browbeat deal 5 damage to them. If no one does, target player draws three cards.

Psychic Strike

Counter target spell. Its controller mills two cards.

Cerebral Vortex

Target player draws two cards, then Cerebral Vortex deals damage to that player equal to the number of cards they've drawn this turn.

Thought Collapse

Counter target spell. Its controller mills three cards.

Arcane Denial

Counter target spell. Its controller may draw up to two cards at the beginning of the next turn's upkeep.
You draw a card at the beginning of the next turn's upkeep.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Bedevil

Destroy target artifact, creature, or planeswalker.

Raven's Crime

Target player discards a card.
Retrace (You may cast this card from your graveyard by discarding a land card in addition to paying its other costs.)

Undermine

Counter target spell. Its controller loses 3 life.

Backlash

Tap target untapped creature. That creature deals damage equal to its power to its controller.

Kolaghan's Command

Choose two —
• Return target creature card from your graveyard to your hand.
• Target player discards a card.
• Destroy target artifact.
• Kolaghan's Command deals 2 damage to any target.

Blightning

Blightning deals 3 damage to target player or planeswalker. That player or that planeswalker's controller discards two cards.

Duress

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