Baleful Mastery

You may pay {1}{B} rather than pay this spell's mana cost.
If the {1}{B} cost was paid, an opponent draws a card.
Exile target creature or planeswalker.

Bloodgift Demon

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

Teferi's Puzzle Box

At the beginning of each player's draw step, that player puts the cards in their hand on the bottom of their library in any order, then draws that many cards.

Sanguine Bond

Whenever you gain life, target opponent loses that much life.

Howling Mine

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

Fate Unraveler

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

Peer into the Abyss

Target player draws cards equal to half the number of cards in their library and loses half their life. Round up each time.

Vito, Thorn of the Dusk Rose

Whenever you gain life, target opponent loses that much life.
{3}{B}{B}: Creatures you control gain lifelink until end of turn.

Dark Deal

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

Decanter of Endless Water

You have no maximum hand size.
{T}: Add one mana of any color.

Marauding Blight-Priest

Whenever you gain life, each opponent loses 1 life.

Lightning Greaves

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.)
Equip {0}

Underworld Dreams

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

Arcane Signet

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

Thought Vessel

You have no maximum hand size.
{T}: Add {C}.

Sign in Blood

Target player draws two cards and loses 2 life.

Font of Mythos

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

Temple Bell

Sheoldred, the Apocalypse

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