msem-instigator

First strike, trample
{2}{R}, Sacrifice a land: Corrignos' Rage gets +3/+0 until end of 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.

Cosmic Catastrophe deals 6 damage to target creature or planeswalker. If you control a creature with power greater than its base power, Cosmic Catastrophe deals 3 damage to each opponent.

Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
Whenever a creature you control enters, if you didn't cast it from your hand, target land you control becomes a 7/1 red Elemental creature with trample and haste. It's still a land.

Gain control of target artifact or creature until end of turn, then untap it. It gains haste until end of turn. You may spend mana as though it were mana of any type to pay the costs of its abilities this turn.

As an additional cost to cast this spell, discard a card.
Draw two cards. The next card you foretell this turn costs {0} to foretell.

Target creature can't block this turn.
Draw a card.

Choose two —
• Destroy target artifact.
• Discard a card, then draw a card.
• Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Wanderlust — This spell costs {2} less to cast as long as you control four or more differently named lands.
Crackle Across Kahembo deals X damage to target creature or planeswalker.

Crafter's Mistake deals 1 damage to target player or planeswalker. That player or that planeswalker's controller sacrifices an artifact.

This spell costs {X} less to cast, where X is 20 minus your life total.
First strike, menace, trample

Prowess
When Cramming Student enters, conjure ten cards named Fatigue and shuffle them into your library. (They're colorless sorceries that cost {2} and have “Draw a card.”)
Instant and sorcery spells you cast cost {1} less to cast.

Target creature gets +X/+0 and gains trample until end of turn.

Creatures you control gain trample until end of turn.
Draw a card.

{1}{R}: Crashcaller Nereid gets +1/+0 and gains trample until end of turn.

Menace (This creature can't be blocked except by two or more creatures.)
Whenever Crazed Bruiser attacks, it gets +2/+0 until end of turn.

Resolute — At the beginning of combat on your turn, if Crazed Swashbuckler's power is greater than its base power, it deals 1 damage to target creature defending player controls. That creature can't block this turn.

Trample
Whenever Crazed Wildlings deals combat damage to a player, create a 1/1 red Goblin creature token.

As an additional cost to cast this spell, discard a nonland card.
Draw two cards.

Whenever you cast a spell for an alternate cost, create two 1/1 red Elemental creature tokens. (This includes “without paying its mana cost.”)
Whenever you cast a red spell from your hand, reveal the top card of your library. If that card has a lesser mana value, you may cast it without paying its mana cost. Otherwise, draw a card, then discard a card.

Bloodprice—Reappropriate red. (You may cast this spell by sacrificing a creature and exiling two red cards from your hand and/or graveyard.)
Haste
Whenever Creed's Desperado attacks, if defending player has more cards in hand than you, exile the top card of that player's library. You may cast it as long as you control a Warrior, and you may spend mana as though it were mana of any color to cast it.

First strike
Whenever Creed, Eternal Straggler attacks, exile the top card of your library. You may play that card this turn, and that spell costs {2} less to cast.

When Crimson Curtain Favored enters, starting with you, each player may discard any number of cards. When each player is finished discarding, choose one —
• Crimson Curtain Favored deals damage to each player equal to the number of cards in their hand.
• Each player draws a card for each card they discarded this way.

Flying, haste
When Crimson Hellmaw enters, it deals 3 damage to any target.
Revive {5}{R}{R} ({5}{R}{R}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Haste
{R}{R}{R}, Discard your hand, Sacrifice Crimson Knight: Draw three cards.