Ob Nixilis, Captive Kingpin

Flying, trample
Whenever one or more opponents each lose exactly 1 life, put a +1/+1 counter on Ob Nixilis. Exile the top card of your library. Until your next end step, you may play that card.

Kederekt Parasite

Whenever an opponent draws a card, if you control a red permanent, you may have this creature deal 1 damage to that player.

Sheoldred, the Apocalypse

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

Propaganda

Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Howling Mine

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

Spiteful Visions

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

Burning Inquiry

Each player draws three cards, then discards three cards at random.

Kami of the Crescent Moon

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

Underworld Dreams

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

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 deals 1 damage to that player.

Fate Unraveler

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

The Locust God

Flying
Whenever you draw a card, create a 1/1 blue and red Insect creature token with flying and haste.
{2}{U}{R}: Draw a card, then discard a card.
When The Locust God dies, return it to its owner's hand at the beginning of the next end step.

No Mercy

Whenever a creature deals damage to you, destroy it.

Koskun Falls

At the beginning of your upkeep, sacrifice this enchantment unless you tap an untapped creature you control.
Creatures can't attack you unless their controller pays {2} for each creature they control that's attacking you.

Temple Bell

Jace's Archivist

{U}, {T}: Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.

Balor

Flying
Whenever this creature attacks or dies, choose one or more. Each mode must target a different player.
• Target opponent draws three cards, then discards three cards at random.
• Target opponent sacrifices a nontoken artifact of their choice.
• This creature deals damage to target opponent equal to the number of cards in their hand.

Dictate of Kruphix

Flash (You may cast this spell any time you could cast an instant.)
At the beginning of each player's draw step, that player draws an additional card.

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, this enchantment deals 2 damage to that player.

Stormfist Crusader

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

Font of Mythos

At the beginning of each player's draw step, that player draws two additional cards.

Zurzoth, Chaos Rider

Whenever an opponent draws their first card each turn, if it's not their turn, you create a 1/1 red Devil creature token with "When this token dies, it deals 1 damage to any target."
Whenever one or more Devils you control attack one or more players, you and those players each draw a card, then discard a card at random.

Ob Nixilis, the Hate-Twisted

Whenever an opponent draws a card, Ob Nixilis deals 1 damage to that player.
−2: Destroy target creature. Its controller draws two cards.

Magus of the Wheel

{1}{R}, {T}, Sacrifice this creature: Each player discards their hand, then draws seven cards.

Psychosis Crawler

Psychosis Crawler's power and toughness are each equal to the number of cards in your hand.
Whenever you draw a card, each opponent loses 1 life.

Folio of Fancies

Players have no maximum hand size.
{X}{X}, {T}: Each player draws X cards.
{2}{U}, {T}: Each opponent mills cards equal to the number of cards in their hand.

Obosh, the Preypiercer

Companion — Your starting deck contains only cards with odd mana values and land cards. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
If a source you control with an odd mana value would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.