Whenever a player finishes exiling cards from anywhere, each opponent loses 1 life.
{2}{B}: Level 2
At the beginning of your upkeep, exile the top card of target opponent's library face down. You may look at it for as long as it remains exiled.
{3}{B}: Level 3
You may cast spells exiled with this Class. Those spells cost {1} less to cast, and mana of any type can be spent to cast those spells.

Lifelink, haste
Whenever Calamity's Cohort attacks, exile the top card of defending player's library. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell. Spend only mana from artifacts to cast that spell.

As an additional cost to cast this spell, sacrifice a creature.
Caldera's Gift deals 3 damage to target creature or planeswalker and you gain 3 life.

You may cast target instant or sorcery card from your graveyard this turn. If that spell would be put into your graveyard, exile it instead.

Whenever an opponent sacrifices a permanent, put a +1/+1 counter on Callous Tactician and that player loses 1 life.
{3}{B}: Each player sacrifices a creature.

Whenever a creature you control dies during your turn, you may exile the top card of your library. You may play that card until you exile another card with Campaign of Retribution.

You may cast creature spells as though they had flash.
At the beginning of your end step, you may shuffle a creature you control into its owner's library. If you do, draw a card, then untap up to two lands.

Whenever you attack, you may cast an Aura card from your graveyard if that spell targets an attacking creature.

Target creature you control gets +2/+0 and gains lifelink until end of turn. When that creature dies this turn, draw a card.

Flying
When Caravan Skyrider enters the battlefield, you may return another permanent you control to its owner's hand.

When Cardboard Box enters the battlefield, draw a card.
Spells that target you cost {2} more to cast.
{T}, Sacrifice Cardboard Box: Untap target creature that's attacking you and remove it from combat.

Deathtouch
When Carrion Viper enters the battlefield, you may discard a card. When you do, return target creature card from your graveyard to your hand.

As an additional cost to cast this spell, discard two cards.
Draw three cards.

When Catscratch Broker enters the battlefield, each opponent sacrifices an enchantment.

When Cawyer Station Veteran dies, you may put a +1/+1 counter on target creature you control.

As an additional cost to cast this spell, exile X creature cards from your graveyard.
Each opponent sacrifices a creature with toughness X or greater.

{3}{G}{W}: Champion of the Many gets +X/+X and gains trample until end of turn, where X is the number of creatures you control.

{4}{W}, Exile Charging Brightmare from your graveyard: Bless target creature. Activate only as a sorcery.

When Chromatic Shard enters the battlefield, draw a card.
{T}, Sacrifice Chromatic Shard: Add one mana of any color.

Cinder Hatchling gets +3/+0 as long as you've cast an instant or sorcery spell with mana value 4 or greater this turn.

Cinderhorn Calf can't block
{1}{R}: Cinderhorn Calf gains menace until end of turn.

Flying
Whenever Cloud Coatl attacks, target player mills two cards.
Reflect {3}{G}

Attacking creatures get +1/+1 until end of turn. If an attacking creature has vigilance, untap all attacking creatures. Then if an attacking creature has flying, all attacking creatures gain flying until end of turn. The same is true for first strike, double strike, deathtouch, hexproof, indestructible, lifelink, menace, and trample.

Whenever Cold Blood attacks, create a first strike Gadget, then attach it to another target attacking creature.
Whenever an enchanted or equipped creature you control becomes the target of a spell or ability an opponent controls, that creature deals damage equal to its power to that player.

{T}, Exile an instant or sorcery card from your graveyard: Add one mana of any type.
Once each turn, when you cast an instant or sorcery spell, you may create a 1/1 colorless Construct artifact creature token.