msem-instigator

Target creature gets -4/-4 until end of turn.

Whenever you cast a noncreature spell, you may shuffle target card an opponent owns in exile into its owner's library.

{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}.

Create a 0/0 blue Construct artifact creature token. Put X +1/+1 counters on it, where X is one plus the total number of noncreature, nonland cards in your graveyard.

Puzzlebox (Begin the game with this and another card you own from outside the game in the command zone, locked. That card is face down until you unlock this.)
Tap four untapped creatures you control: Unlock Clockwork Astrolarium. If the revealed card is white, put it into your hand. Otherwise, put it on top of your library.

When Cloister enters, exile another target nonland permanent you control and target nonland permanent you don't control until Cloister leaves the battlefield.
{2}{W}, Sacrifice Cloister: You gain 5 life.

Target creature gets +2/+0 until end of turn and can't be blocked this turn.

Trample
You may spend black and green mana as though it were mana of any color.
Whenever Closing-Act Abomination attacks, look at the top X cards of your library, where X is the number of colors among cards in your graveyard. Put up to one of them into your hand and the rest on the bottom of your library in a random order.

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
At the beginning of your end step, you may untap another target permanent.

Stampede — Whenever Cloud's Roar Avenger and a creature with greater power attack, tap up to one target creature.

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

Flying
When Cloudchaser Kestrel enters, destroy target enchantment.
{W}: Target permanent becomes white until end of turn.

Counter target spell. If that spell is countered this way, put it into its owner's hand instead of into that player's graveyard. That player mills three cards.

Flying
When Cloudheath Sentinel enters, return target artifact card with mana value 2 or less from your graveyard to the battlefield.

({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}.”

Flying
When Cloudshaper enters, return a permanent you control to its owner's hand.

Flying, lifelink
When Cloudshaper Pilgrim enters, return target creature or enchantment card with mana value 3 or less from your graveyard to your hand.

Return target creature to its owner's hand.
Kindle 1—{U} ({U}, Exile this card from your graveyard: Create a 1/1 colorless Elemental creature token. Kindle only as a sorcery.)

Heretic (Whenever you cast a spell that doesn't share a color with this creature, it gets +1/+1 until end of turn.)
Whenever you cast a spell that doesn't share a color with Cloudstep Capuchin, Cloudstep Capuchin gains flying and hexproof until end of turn.

Flying
{3}{R}, {T}: Cloudwing deals 2 damage to target creature. You may tap or untap that creature.

Clutch Shot deals 2 damage to target creature or planeswalker. If you control six or more lands, Clutch Shot deals 4 damage instead.

Return target creature to its owner's hand.
Coalesce {4}{U}{U} (You may cast this from your graveyard for {4}{U}{U}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)

{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.

Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Coalition Alchemist enters deployed, return target instant or sorcery card from your graveyard to your hand.