msem-instigator

Menace, haste
Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)

When Cabinet of Curiosities enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead.

Defender, reach
Sacrifice Cackling Jack: It deals 3 damage to any target.

Haste
Revive {3}{R} ({3}{R}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost. Activate this ability only any time you could cast a sorcery.)

Whenever one or more cards are put into an opponent's graveyard from their hand or library, Cackling Tormentor deals 2 damage to any target.

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature you don't control blocks, Cadalon Chemist deals 1 damage to that creature.

When Cadalon Experimenter enters, if you control an artifact, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

When Caer Crann Borderscout enters, you may search your library for a basic land card, reveal it, and put it into your hand. If you do, shuffle.

When Caer Crann Warleader enters, distribute three +1/+1 counters among any number of creatures you control.
Embattled creatures you control have trample. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

At the beginning of each opponent's upkeep, if that player has no cards in their hand, Cage of Torment deals 2 damage to that player.

During your turn, cards in your hand have cycling {X}, where X is the number of cards you've discarded this turn.
At the beginning of each end step, create a 1/1 blue Tentacle creature token for each card you discarded this turn.
Cycling {R} ({R}, Discard this card: Draw a card.)

Destroy all artifacts with mana value X or less. Whenever an artifact is destroyed this way, Calamitous Crash deals 1 damage to any target.

Calamitous Rampage deals 5 damage to any target.
Cycling {G} ({G}, Discard this card: Draw a card.)

Flying
When Calamity Dragon enters, it deals 2 damage to each creature you don't control. Whenever a creature dealt damage this way dies this turn, Calamity Dragon deals 2 damage to that creature's controller.

Whenever Calamity Scholar attacks, if you control an artifact, put a +1/+1 counter on it.

I — Exile the top card of your library face down.
II — Exile any number of cards from your hand face down.
III — Calamity of Yore deals damage to target creature or planeswalker equal to the number of cards you own in exile. Return all cards exiled with Calamity of Yore to their owners' hands.

Target creature or planeswalker you control explores. (Reveal the top card of your library. Put it into your hand if it's a land. Otherwise, put a +1/+1 or loyalty counter on that permanent, then you may put that card into your graveyard.)

This spell can't be countered.
Search your library for a basic land or a Hydra card not named Aurora Hydra, reveal it, and put it into your hand. Then shuffle.

Search your library for a Dragon card, reveal it, put it into your hand, then shuffle. It deals damage equal to its power to you.

Recruit. (Create a 0/0 white Soldier Army creature token, then put a +1/+1 counter on each Army you control.)
Armies you control gain trample until end of turn.

Create a 1/1 colorless Construct Actor creature token. Put a +1/+1 counter on it if you control another Construct.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

Sacrifice a permanent, then draw cards equal to its mana value.
You may put a permanent card from your hand onto the battlefield if its mana value is less than or equal to the number of cards in your hand.

Destroy up to one target creature with flying or enchantment. 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.”)

{1}{G}{G}, Sacrifice a creature: Search your library for a creature card with mana value X or less, where X is 1 plus the sacrificed creature's mana value. Put that card onto the battlefield, then shuffle. Activate only as a sorcery.

First strike
Whenever you make first contact, Callous Conduit deals 1 damage to target player or planeswalker. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)