Ruthless Sniper

Whenever you cycle or discard a card, you may pay {1}. If you do, put a -1/-1 counter on target creature.

Cryptcaller Chariot

Menace
Whenever you discard one or more cards, create that many tapped 2/2 black Zombie creature tokens.
Crew 2

Magmakin Artillerist

Whenever you discard one or more cards, this creature deals that much damage to each opponent.
Cycling {1}{R} ({1}{R}, Discard this card: Draw a card.)
When you cycle this card, it deals 1 damage to each opponent.

Glint-Horn Buccaneer

Haste
Whenever you discard a card, this creature deals 1 damage to each opponent.
{1}{R}, Discard a card: Draw a card. Activate only if this creature is attacking.

Hostile Investigator

When this creature enters, target opponent discards a card.
Whenever one or more players discard one or more cards, investigate. This ability triggers only once each turn. (Create a Clue token. It's an artifact with "{2}, Sacrifice this token: Draw a card.")

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.

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.

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.)

Marauding Mako

Whenever you discard one or more cards, put that many +1/+1 counters on this creature.
Cycling {2} ({2}, Discard this card: Draw a card.)

Monument to Endurance

Whenever you discard a card, choose one that hasn't been chosen this turn —
• Draw a card.
• Create a Treasure token.
• Each opponent loses 3 life.

Ivora, Insatiable Heir

Trample
When Ivora enters and whenever it deals combat damage to a player, create a Blood token. (It's an artifact with "{1}, {T}, Discard a card, Sacrifice this token: Draw a card.")
Whenever you discard a card, put a +1/+1 counter on Ivora.

Soul of Windgrace

Whenever Soul of Windgrace enters or attacks, you may put a land card from a graveyard onto the battlefield tapped under your control.
{G}, Discard a land card: You gain 3 life.
{1}{R}, Discard a land card: Draw a card.
{2}{B}, Discard a land card: Soul of Windgrace gains indestructible until end of turn. Tap it.

Feast of Sanity

Whenever you discard a card, this enchantment deals 1 damage to any target and you gain 1 life.

Surly Badgersaur

Whenever you discard a creature card, put a +1/+1 counter on this creature.
Whenever you discard a land card, create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")
Whenever you discard a noncreature, nonland card, this creature fights up to one target creature you don't control.

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.

Brallin, Skyshark Rider

Partner with Shabraz, the Skyshark (When this creature enters, target player may put Shabraz into their hand from their library, then shuffle.)
Whenever you discard a card, put a +1/+1 counter on Brallin and it deals 1 damage to each opponent.
{R}: Target Shark gains trample until end of turn.