Chamber Sentry enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it.
, , Remove X +1/+1 counters from Chamber Sentry: It deals X damage to any target.
: Return Chamber Sentry from your graveyard to your hand.

Charcoal Diamond enters the battlefield tapped.
: Add .

Chimeric Mass enters the battlefield with X charge counters on it.
: Until end of turn, Chimeric Mass becomes a Construct artifact creature with "This creature's power and toughness are each equal to the number of charge counters on it."

Flying
When Chipper Chopper enters the battlefield, you may sacrifice another artifact. If you do, put two +1/+1 counters on Chipper Chopper and it assembles a Contraption. (Put the top card of your Contraption deck face up onto one of your sprockets.)

Flying
When Chivalrous Chevalier enters the battlefield, return a creature you control to its owner's hand unless you compliment an opponent.

Imprint — When Chrome Mox enters the battlefield, you may exile a nonartifact, nonland card from your hand.
: Add one mana of any of the exiled card's colors.

When Chrome Replicator enters the battlefield, if you control two or more nonland, nontoken permanents with the same name as one another, create a 4/4 colorless Construct artifact creature token.

When Chronobot enters the battlefield, switch upkeep steps with target opponent for as long as it remains on the battlefield. (You take your upkeep on their turn, and they take their upkeep on your turn.)

Sunburst (This enters the battlefield with a charge counter on it for each color of mana spent to cast it.)
At the beginning of your upkeep, you may gain life equal to the number of charge counters on Clearwater Goblet.

When Cliffhaven Kitesail enters the battlefield, attach it to target creature you control.
Equipped creature has flying.
Equip (: Attach to target creature you control. Equip only as a sorcery.)

Equipped creature gets +2/+0 and has shroud. (It can't be the target of spells or abilities.)
Whenever a Rogue creature enters the battlefield, you may attach Cloak and Dagger to it.
Equip

Flying
Clockwork Avian enters the battlefield with four +1/+0 counters on it.
At end of combat, if Clockwork Avian attacked or blocked this combat, remove a +1/+0 counter from it.
, : Put up to X +1/+0 counters on Clockwork Avian. This ability can't cause the total number of +1/+0 counters on Clockwork Avian to be greater than four. Activate this ability only during your upkeep.

Clockwork Beast enters the battlefield with seven +1/+0 counters on it.
At end of combat, if Clockwork Beast attacked or blocked this combat, remove a +1/+0 counter from it.
, : Put up to X +1/+0 counters on Clockwork Beast. This ability can't cause the total number of +1/+0 counters on Clockwork Beast to be greater than seven. Activate this ability only during your upkeep.

Clockwork Beetle enters the battlefield with two +1/+1 counters on it.
Whenever Clockwork Beetle attacks or blocks, remove a +1/+1 counter from it at end of combat.

Flying
Clockwork Condor enters the battlefield with three +1/+1 counters on it.
Whenever Clockwork Condor attacks or blocks, remove a +1/+1 counter from it at end of combat.

Flying
Clockwork Dragon enters the battlefield with six +1/+1 counters on it.
Whenever Clockwork Dragon attacks or blocks, remove a +1/+1 counter from it at end of combat.
: Put a +1/+1 counter on Clockwork Dragon.

Clockwork Hydra enters the battlefield with four +1/+1 counters on it.
Whenever Clockwork Hydra attacks or blocks, remove a +1/+1 counter from it. If you do, Clockwork Hydra deals 1 damage to any target.
: Put a +1/+1 counter on Clockwork Hydra.

Adamant — When Clockwork Servant enters the battlefield, if at least three mana of the same color was spent to cast it, draw a card.

Clockwork Steed enters the battlefield with four +1/+0 counters on it.
Clockwork Steed can't be blocked by artifact creatures.
At end of combat, if Clockwork Steed attacked or blocked this combat, remove a +1/+0 counter from it.
, : Put up to X +1/+0 counters on Clockwork Steed. This ability can't cause the total number of +1/+0 counters on Clockwork Steed to be greater than four. Activate this ability only during your upkeep.

Clockwork Swarm enters the battlefield with four +1/+0 counters on it.
Clockwork Swarm can't be blocked by Walls.
At end of combat, if Clockwork Swarm attacked or blocked this combat, remove a +1/+0 counter from it.
, : Put up to X +1/+0 counters on Clockwork Swarm. This ability can't cause the total number of +1/+0 counters on Clockwork Swarm to be greater than four. Activate this ability only during your upkeep.