Call the Bloodline

{1}, Discard a card: Create a 1/1 black Vampire Knight creature token with lifelink. Activate only once each turn.

Archfiend of Ifnir

Flying
Whenever you cycle or discard another card, put a -1/-1 counter on each creature your opponents control.
Cycling {2} ({2}, Discard this card: Draw a card.)

Liliana, Waker of the Dead

+1: Each player discards a card. Each opponent who can't loses 3 life.
−3: Target creature gets -X/-X until end of turn, where X is the number of cards in your graveyard.
−7: You get an emblem with "At the beginning of combat on your turn, put target creature card from a graveyard onto the battlefield under your control. It gains haste."

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.

Icatian Crier

{1}{W}, {T}, Discard a card: Create two 1/1 white Citizen creature tokens.

Avenger en-Dal

{2}{W}, {T}, Discard a card: Exile target attacking creature. Its controller gains life equal to its toughness.

Cunning Lethemancer

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

Gibbering Descent

At the beginning of each player's upkeep, that player loses 1 life and discards a card.
Hellbent — Skip your upkeep step if you have no cards in hand.
Madness {2}{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.)

Bottomless Pit

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

Ravos, Soultender

Flying
Other creatures you control get +1/+1.
At the beginning of your upkeep, you may return target creature card from your graveyard to your hand.
Partner (You can have two commanders if both have partner.)

Gilt-Blade Prowler

{1}, {T}, Pay 1 life: Draw a card. Activate only if you've discarded a card this turn.

Bone Miser

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

Cho-Arrim Alchemist

{1}{W}{W}, {T}, Discard a card: The next time a source of your choice would deal damage to you this turn, prevent that damage. You gain life equal to the damage prevented this way.

Feast of Sanity

Whenever you discard a card, Feast of Sanity deals 1 damage to any target and you gain 1 life.

Delirium Skeins

Devout Witness

{1}{W}, {T}, Discard a card: Destroy target artifact or enchantment.

Anvil of Bogardan

Players have no maximum hand size.
At the beginning of each player's draw step, that player draws an additional card, then discards a card.

Dying to Serve

Whenever you discard one or more cards, create a tapped 2/2 black Zombie creature token. This ability triggers only once each turn.

Bog Witch

Tormod, the Desecrator

Whenever one or more cards leave your graveyard, create a tapped 2/2 black Zombie creature token.
Partner (You can have two commanders if both have partner.)

Faith of the Devoted

Whenever you cycle or discard a card, you may pay {1}. If you do, each opponent loses 2 life and you gain 2 life.