You may exile a red card from your hand rather than pay this spell's mana cost.
Cave-In deals 2 damage to each creature and each player.

Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)
: Cavern Crawler gets +1/-1 until end of turn.

When Ceremonial Guard attacks or blocks, destroy it at end of combat.

Whenever Chambered Nautilus becomes blocked, you may draw a card.

As Chameleon Spirit enters the battlefield, choose a color.
Chameleon Spirit's power and toughness are each equal to the number of permanents of the chosen color your opponents control.

Enchant creature
Whenever enchanted creature deals damage to a creature, gain control of the other creature for as long as Charisma remains on the battlefield.

, , Discard a card: The next time a source of your choice would deal damage to target creature this turn, prevent that damage.

Flying
When Charmed Griffin enters the battlefield, each other player may put an artifact or enchantment card onto the battlefield from their hand.

, , Discard a card: The next time a source of your choice would deal damage to you this turn, prevent that damage. You gain life equal to the damage prevented this way.

Whenever Cho-Arrim Bruiser attacks, you may tap up to two target creatures.

If an opponent controls a Swamp and you control a Plains, you may cast this spell without paying its mana cost.
Protection from black

Flash
Enchant creature
As Cho-Manno's Blessing enters the battlefield, choose a color.
Enchanted creature has protection from the chosen color. This effect doesn't remove Cho-Manno's Blessing.

Prevent all damage that would be dealt to Cho-Manno, Revolutionary.

, , Sacrifice Cinder Elemental: It deals X damage to any target.

Each player reveals the top five cards of their library, puts all land cards revealed this way onto the battlefield tapped, and exiles the rest.

Whenever a creature you control becomes blocked, Close Quarters deals 1 damage to any target.

Flying (This creature can't be blocked except by creatures with flying or reach.)
Cloud Sprite can block only creatures with flying.

Whenever a creature you control deals combat damage to an opponent, you may draw a card.

Draw a card for each creature you control.

Nonartifact creatures get +2/+2 as long as they all share a color.