Enchant creature
Enchanted creature gets +1/+1 and has “Whenever this creature deals combat damage to a player, draw a card.”
{VP}{VP}{VP}: Enchanted creature gains flying until end of turn.

Enchant creature
Whenever enchanted creature deals combat damage to a player or planeswalker, you may sacrifice it. If you do, untap all creatures you control and after this phase, there is an additional combat phase.

Enchant creature
When Contain for Study enters, tap enchanted creature.
You control enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

When Contest Coordinator enters, look at the top five cards of your library. You may reveal a Plains card or a nonland card with an activated ability from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

Once each turn, when you activate an ability of a creature you control, untap that creature and put a +1/+1 counter on it.

Once each turn, when you activate a nonmana ability, you gain 2 life.

{T}, Tap another untapped creature you control: You may tap or untap another target creature.
Whenever Contest Star becomes untapped, draw a card.

Controlled Ecosystem enters tapped.
{T}: Add {G} or {U}.
{4}: Make a pledge. Activate only as a sorcery.

You may look at the top card of your library any time.
You may cast artifact and enchantment spells from the top of your library.
{T}, Sacrifice three artifacts and/or enchantments: Search your library for a card, then shuffle and put that card on top.

Corgan Bourgeois's power is equal to the number of artifacts you control.
Whenever Corgan Bourgeois or another artifact you control enters, you gain 1 life.

Whenever a creature dies, scry 1.

Corgan Sprawl enters tapped.
{T}: Add {B} or {R}.
{T}, Discard another card named Corgan Sprawl: Draw a card.

Whenever a creature you control deals combat damage to a player, you may sacrifice it. If you do, draw a card. Otherwise, surveil 1.

Menace
Whenever Corporate Mentor attacks, teach target attacking creature with lesser power menace.

Choose one —
• Return target creature card from a graveyard to its owner's hand.
• Exile target creature card in a graveyard, then draw a card.

{C/B}: Integrate target card in a graveyard.
As long as a creature card with flying is integrated onto Corpsepyre Fiend, it has flying. The same is true for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, reach, trample, and vigilance.

Flash
When Corrosive Spitter enters, destroy all creatures that were dealt damage this turn.

Whenever Corrupt Congressman enters or attacks, make a pledge.
Cliques you control have “Pledge — {4}: Each opponent loses 3 life unless they discard a card or sacrifice a creature. Activate only as a sorcery.”

When Cosmic Colossus enters, if you cast it from your hand, cast a copy of target card in exile without paying its mana cost unless an opponent exiles two nonland permanents they control.

Choose up to X target creatures. Switch their power and toughness until end of turn.
All creatures get -3/-3 until end of turn.

Menace
When Covert Infiltrator is put into your graveyard from your library, you may pay 2 life. If you do or if you control a blue permanent, return this card to your hand.

Flying, ward {1}
Whenever you cast an instant or sorcery spell, mill a card. Return an instant or sorcery card milled this way to your hand. If you can't, put a +1/+1 counter on Covetous Frostwyrm.

{2}, Sacrifice another creature: Put a +1/+1 counter on Coward-Eater. Draw a card.

{T}: Add {C}.
{1}, {T}, Sacrifice Cradle of Rebirth: Copy target spell you control which had its flashback cost paid. You may choose new targets for the copy.

{T}: Add one mana of any color.
{T}: Draw a card, then discard a card. Activate only if you've cast a non-Human creature spell this turn.