You can't cast noncreature spells.
Creature spells you cast cost {X} less to cast, where X is the greatest power among creatures you control.

Reach
Bumbling Bigfoot doesn't untap during your untap step.
Wander {1}{G}{G}

Drop — When Bumping Betta enters, if you didn't cast any creature spells during your last turn, return up to one target nonland permanent to its owner's hand.

At the beginning of your end step, if a creature card or creature token was put into your graveyard from anywhere this turn, surveil 1.

Vigilance
Whenever Bureau Mentor attacks, teach target attacking creature with lesser power vigilance. Untap that creature.

Choose one —
• Search your library for a land card, put it onto the battlefield tapped, then shuffle.
• Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Buried Colossus enters tapped.
{T}: Add {G} or {W}.
{8}{G/W}: Buried Colossus becomes a 8/8 green and white Cyclops creature until end of turn. It's still a land. This ability costs {X} less to activate, where X is your devotion to green and white. Activate only once each turn.

All spells cost {1} more to cast.
Spellcharge 6

Burn Rubber deals 1 damage to each creature your opponents control. Creatures your opponents control can't block this turn.

Flying, haste
Whenever you cast an instant or sorcery spell with mana value 4 or greater, you may return Burning Witch to its owner's hand. If you do, copy that spell. You may choose new targets for the copy.

Bustling Motorway enters tapped.
{T}: Add {U} or {R}.
{4}: Make a pledge. Activate only as a sorcery.

Counter target spell unless its controller pays {2}. Until end of turn, spells your opponents cast cost {1} more to cast.

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.

Approval — When Cabinet Recruiter enters, you may search your library for a creature card with mana value less than or equal to the number of colors among permanents you control, reveal it, put it into your hand, then shuffle.

When Cairnblade of the Ancients enters, destroy target creature an opponent controls.
Equipped creature gets +4/+2 and has vigilance.
Equip {4}

Calamitous War Cry deals 2 damage to each creature. If there are six or more different creature types among creatures you control as you cast this spell, it deals 2 damage to each creature you don't control instead.

Callaphe can't be blocked by creatures with mana value 4 or greater.
Whenever Callaphe the Mariner deals combat damage to a player, you get an experience counter. Then if you have three or more experience counters, bless target player.

When Caller of Ferocity enters, bless target creature.

Counter all other spells. Exile up to one spell countered this way instead of putting it into its owner's graveyard. You may cast that spell for as long as it remains exiled, and mana of any type can be spent to cast it.

At the beginning of your upkeep, exile the top card of target opponent's library. You may play that card for as long as it remains exiled, and mana of any type can be spent to cast it.
Spells you cast and don't own cost {1} less to cast.

Whenever you attack, draw a card for each attacking creature with power 4 or greater, then put a +1/+1 counter on each attacking creature with power 3 or less.

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.

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

Sacrifice a Treasure: Capital Maglev gains your choice of haste or trample until end of turn.
Crew 2

Flying
Whenever Capital Skyraiders deals combat damage to a player, integrate the top card of that player's library.
Capital Skyraiders gets +3/+3 as long as four or more cards are integrated onto it.