Ghostly Castigator

Flying
When Ghostly Castigator enters, you may shuffle up to three target cards from your graveyard into your library.
If Ghostly Castigator would be put into a graveyard from anywhere, exile it instead.

Covetous Castaway

When Covetous Castaway dies, mill three cards. (Put the top three cards of your library into your graveyard.)
Disturb {3}{U}{U} (You may cast this card from your graveyard transformed for its disturb cost.)

Covetous Castaway // Ghostly Castigator

Illusion of Choice

You choose how each player votes this turn.
Draw a card.

Ashmouth Dragon

Flying
Whenever you cast an instant or sorcery spell, Ashmouth Dragon deals 2 damage to any target.

Smoldering Egg

Defender
Whenever you cast an instant or sorcery spell, put a number of ember counters on Smoldering Egg equal to the amount of mana spent to cast that spell. Then if Smoldering Egg has seven or more ember counters on it, remove them and transform Smoldering Egg.

Smoldering Egg // Ashmouth Dragon

Voracious Reader

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Instant and sorcery spells you cast cost {1} less to cast.

Curious Homunculus

{T}: Add {C}. Spend this mana only to cast an instant or sorcery spell.
At the beginning of your upkeep, if there are three or more instant and/or sorcery cards in your graveyard, transform Curious Homunculus.

Curious Homunculus // Voracious Reader

Perfected Form

Aberrant Researcher

Flying
At the beginning of your upkeep, mill a card. If an instant or sorcery card was milled this way, transform Aberrant Researcher.

Aberrant Researcher // Perfected Form

Mercurial Spelldancer

Mercurial Spelldancer can't be blocked.
Whenever you cast a noncreature spell, put an oil counter on Mercurial Spelldancer.
Whenever Mercurial Spelldancer deals combat damage to a player, you may remove two oil counters from it. If you do, when you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

Plea for Power

Will of the council — Starting with you, each player votes for time or knowledge. If time gets more votes, take an extra turn after this one. If knowledge gets more votes or the vote is tied, draw three cards.

Mountain

Dress Down

Flash
When Dress Down enters, draw a card.
Creatures lose all abilities.
At the beginning of the end step, sacrifice Dress Down.

Island

Biolume Serpent

Sacrifice two Islands: Biolume Serpent can't be blocked this turn.

Biolume Egg

Defender
When Biolume Egg enters, scry 2.
When you sacrifice Biolume Egg, return it to the battlefield transformed under its owner's control at the beginning of the next end step.

Biolume Egg // Biolume Serpent

Homicidal Brute

At the beginning of your end step, if Homicidal Brute didn't attack this turn, tap Homicidal Brute, then transform it.

Civilized Scholar

{T}: Draw a card, then discard a card. If a creature card is discarded this way, untap Civilized Scholar, then transform it.

Civilized Scholar // Homicidal Brute

Alexander Clamilton

Whenever you cast a wordy spell, scry 2. (A spell is wordy if it has four or more lines of rules text.)
{1}{R}, {T}: Choose target creature you don't control. Reveal the top card of your library. Alexander Clamilton gets +X/+0 until end of turn, where X is the number of lines of rules text of the revealed card. Alexander Clamilton fights that creature.

Chrome Host Seedshark

Flying
Whenever you cast a noncreature spell, incubate X, where X is that spell's mana value. (Create an Incubator token with X +1/+1 counters on it and "{2}: Transform this artifact." It transforms into a 0/0 Phyrexian artifact creature.)

Awoken Horror

When this creature transforms into Awoken Horror, return all non-Horror creatures to their owners' hands.

Thing in the Ice

Defender
Thing in the Ice enters with four ice counters on it.
Whenever you cast an instant or sorcery spell, remove an ice counter from Thing in the Ice. Then if it has no ice counters on it, transform it.

Thing in the Ice // Awoken Horror

Final Iteration

Flying
Wizards you control get +2/+1 and have flying.
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token.

Docent of Perfection

Flying
Whenever you cast an instant or sorcery spell, create a 1/1 blue Human Wizard creature token. Then if you control three or more Wizards, transform Docent of Perfection.

Docent of Perfection // Final Iteration

Conqueror's Foothold

(Transforms from Conqueror's Galleon.)
{T}: Add {C}.
{2}, {T}: Draw a card, then discard a card.
{4}, {T}: Draw a card.
{6}, {T}: Return target card from your graveyard to your hand.

Conqueror's Galleon

When Conqueror's Galleon attacks, exile it at end of combat, then return it to the battlefield transformed under your control.
Crew 4 (Tap any number of creatures you control with total power 4 or more: This Vehicle becomes an artifact creature until end of turn.)

Conqueror's Galleon // Conqueror's Foothold

Insectile Aberration

Delver of Secrets

At the beginning of your upkeep, look at the top card of your library. You may reveal that card. If an instant or sorcery card is revealed this way, transform Delver of Secrets.