msem-instigator

When Coralight Paladin enters, you may search your library for an artifact card, reveal it, then shuffle and put that card on top.
Concord — Whenever Coralight Paladin attacks, if there are four or more card types among permanents you control, Merfolk you control get +1/+1 until end of turn.

Vigilance
When Coralight Sentinel enters, create a white Aura enchantment token named Crab's Resolve attached to target creature. The token has enchant creature and “Enchanted creature gets +0/+2.”

Reach
When Cordial Ticketmaster enters, put a +1/+1 counter on target creature.

Core Ignition deals X damage to target creature or planeswalker.
Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

Choose one —
• Target permanent gains indestructible and lifelink until end of turn.
• Exile target enchantment with mana value 3 or less.

This spell costs {1} less to cast for each artifact you control.
Draw three cards, then Corecharge deals damage to any target equal to the number of cards in your hand.

{T}, Remove a +1/+1 counter from a creature you control: You draw a card and you lose 1 life.

({T}: Add {B}.)
Corpsebed enters tapped.
When Corpsebed enters, exile up to two target cards from graveyards.

Whenever another Zombie or Demon creature you control enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Menace
Whenever you cast an instant or sorcery spell, create a 2/2 black Zombie creature token. This ability triggers only once each turn.

When target creature you control dies this turn, return it or another creature card with an equal or lesser mana value from your graveyard to the battlefield tapped.

Return target creature or planeswalker card from your graveyard to the battlefield. If that card was a creature, it's an Actor in addition to its other types.

When Corrupt Warden enters, up to one target creature gets -X/-X until end of turn, where X is the number of card types among cards in your graveyard.

This spell costs {1} less to cast for each card type among cards in your graveyard.
Deathtouch

Flying
{1}{B}, {T}: Destroy target creature that was dealt damage this turn.

Rhapsody {5}{R}{R} (Pay {5}{R}{R} to cast this as a 4/4, or as a sorcery to make it become a 4/4.)
When Corrupted Guardian enters, it deals damage equal to its power to up to one target player or planeswalker.

Surveil 2, then you draw a card and you lose 1 life. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
{2}{B}, Exile Corrupted Knowledge from your graveyard: Each opponent loses 2 life and you gain 2 life.

Glitch {1} (Remove one [restriction] for each time you pay the glitch cost.)
Target opponent reveals their hand. You choose a [noncreature,] nonland card [with mana value 3 or less] from among them. That player discards that card.

(Transform this if it's not attached to a creature. Pay {3}{B} as a sorcery to unattach it.)
Enchant creature you control
Corrupted Mount's rider gets +5/+4 and can't block.

Whenever an opponent casts a spell, that player gets a poison counter unless they pay {1}.
As long as an opponent has five or more poison counters, Corrupted Soothsayer gets +2/+1 and has flying.

Enchant creature
Enchanted creature gets +3/-2.

Enchant creature
Enchanted creature gets -3/-3 and has “At the beginning of your upkeep, you lose 3 life.”

Corsair Sellsword can't block.
Whenever you foretell a card or cast a foretold spell, you may return Corsair Sellsword from your graveyard to your hand.

Living weapon (When this Equipment enters, create a 0/0 black Phyrexian Germ creature token, then attach this to it.)
Equipped creature gets +1/-1.
Whenever equipped creature dies, draw a card. This ability triggers only once each turn.
Equip {1}

Melee (Whenever this creature attacks, it gets +1/+1 until end of turn for each opponent you attacked this combat.)
Corym's Elite can't be blocked by creatures with power 2 or less.