msem-instigator

Whenever you cast an instant or sorcery spell, you may exile that card instead of putting it anywhere else as it resolves.
At the beginning of your upkeep, Clash Reactor deals X damage to each opponent, where X is the number of colors of cards exiled with Clash Reactor.

Exile target nonland permanent.

{T}, Pay 1 life: Add {W} or {U}.
{1}, {T}, Sacrifice Cleared Vault: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Cliffside Entrance enters tapped unless you have 15 or less life.
{T}: Add {R} or {W}.

Equipped creature has flying.
Equip {3}

Equipped creature has hexproof. (That creature can't be the target of spells or abilities your opponents control.)
Equip {0}

{T}, Tap an untapped creature you control: Choose one —
• Add one mana of any color.
• Target player loses 2 life.
• Target player gains 3 life.
• Target player mills four cards.

Clocktower Hideout enters tapped.
When Clocktower Hideout enters, look at the top card of your library. You may put it into your graveyard.
{T}: Add {B} or {R}.

Clockwork Gaucho enters with a +1/+1 counter on it.
Other artifact creatures you control get +1/+1 for each +1/+1 counter on Clockwork Gaucho.
{T}: Put a +1/+1 counter on Clockwork Gaucho.

{T}: Add {C}.
{T}, Pay 1 life: Add {W} or {B}.

({T}: Add {U}.)
Cloudbank enters tapped.
When Cloudbank enters, target creature gains flying until end of turn.

Cloudcover Heights enters tapped unless you control a Forest.
{T}: Add {R} or {W}.

({T}: Add {R}.)
As Cloudpeak Spires enters, you may pay 1 life. If you don't, Cloudpeak Spires enters tapped.
Basic lands you control have “{T}: Add {R}.”

({T}: Add {R} or {W}.)
Cloudsteel Summit enters tapped.
{1}, {T}: Add {R}{R} or {W}{W}.

{T}: Add {C}.
{1}: Clutch of the Coil becomes a 1/1 Snake creature with poisonous 2 until end of turn. It's still a land. (Whenever this creature deals combat damage to a player, that player gets two poison counters.)

{1}, {T}: Draw a card, then exile a card from your hand face down until Cluttered Study leaves the battlefield. (It returns to your hand.)
{3}, {T}: Shuffle Cluttered Study into its owner's library.

{T}: Add one mana of any color.
{T}: Put a charge counter on Coalition Relic.
At the beginning of your first main phase, remove all charge counters from Coalition Relic. Add one mana of any color for each charge counter removed this way.

({T}: Add {W}, {U}, or {B}.)
Coastal Dominion enters tapped.

Coastal Metropolis enters tapped unless you have 15 or less life.
{T}: Add {W} or {U}.

When Cobbled Currency enters, discard a card, then draw a card.
{3}, Sacrifice Cobbled Currency: Discard two cards, then draw two cards.

Trample, haste
Crew—Tap three untapped artifacts and/or creatures you control.

Equipped creature has flying.
Equip {1} ({1}: Attach to target creature you control. Equip only as a sorcery.)

Extort (Whenever you cast a spell, you may pay {W/B}. If you do, each opponent loses 1 life and you gain that much life.)
Other artifacts you control have extort.
Whenever a spell you control resolves, if it was extorted three or more times, each opponent discards a card and you draw a card.

When Collapsing Frame enters, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
{2}, Sacrifice Collapsing Frame: Draw a card.

{T}: Add {C}.
{1}, {T}, Return Collapsing Ground to its owner's hand: Add one mana of any color.