Dire Fleet Ravager

Menace, deathtouch
When Dire Fleet Ravager enters, each player loses a third of their life, rounded up.

Yawgmoth, Thran Physician

Protection from Humans
Pay 1 life, Sacrifice another creature: Put a -1/-1 counter on up to one target creature and draw a card.
{B}{B}, Discard a card: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Galecaster Colossus

Tap an untapped Wizard you control: Return target nonland permanent you don't control to its owner's hand.

Molten Echoes

As Molten Echoes enters, choose a creature type.
Whenever a nontoken creature you control of the chosen type enters, create a token that's a copy of that creature. That token gains haste. Exile it at the beginning of the next end step.

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Beguiler of Wills

{T}: Gain control of target creature with power less than or equal to the number of creatures you control.

Sundial of the Infinite

{1}, {T}: End the turn. Activate only during your turn. (Exile all spells and abilities from the stack. Discard down to your maximum hand size. Damage wears off, and "this turn" and "until end of turn" effects end.)

Volcanic Offering

Destroy target nonbasic land you don't control and target nonbasic land of an opponent's choice you don't control.
Volcanic Offering deals 7 damage to target creature you don't control and 7 damage to target creature of an opponent's choice you don't control.

Trophy Mage

When Trophy Mage enters, you may search your library for an artifact card with mana value 3, reveal it, put it into your hand, then shuffle.

Panharmonicon

If an artifact or creature entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Sneak Attack

{R}: You may put a creature card from your hand onto the battlefield. That creature gains haste. Sacrifice the creature at the beginning of the next end step.

Sower of Temptation

Flying
When Sower of Temptation enters, gain control of target creature for as long as Sower of Temptation remains on the battlefield.

Exclusion Mage

When this creature enters, return target creature an opponent controls to its owner's hand.

Thassa, Deep-Dwelling

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of your end step, exile up to one other target creature you control, then return that card to the battlefield under your control.
{3}{U}: Tap another target creature.

Puppeteer Clique

Flying
When Puppeteer Clique enters, put target creature card from an opponent's graveyard onto the battlefield under your control. It gains haste. At the beginning of your next end step, exile it.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Inalla, Archmage Ritualist

Eminence — Whenever another nontoken Wizard you control enters, if Inalla, Archmage Ritualist is in the command zone or on the battlefield, you may pay {1}. If you do, create a token that's a copy of that Wizard. The token gains haste. Exile it at the beginning of the next end step.
Tap five untapped Wizards you control: Target player loses 7 life.

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

Anathemancer

When Anathemancer enters, it deals damage to target player equal to the number of nonbasic lands that player controls.
Unearth {5}{B}{R} ({5}{B}{R}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Disciple of Bolas

When Disciple of Bolas enters, sacrifice another creature. You gain X life and draw X cards, where X is that creature's power.

Tribute Mage

When Tribute Mage enters, you may search your library for an artifact card with mana value 2, reveal that card, put it into your hand, then shuffle.

Dualcaster Mage

Flash
When Dualcaster Mage enters, copy target instant or sorcery spell. You may choose new targets for the copy.

Naban, Dean of Iteration

If a Wizard you control entering causes a triggered ability of a permanent you control to trigger, that ability triggers an additional time.

Bloodline Necromancer

Lifelink
When Bloodline Necromancer enters, you may return target Vampire or Wizard creature card from your graveyard to the battlefield.

Urza's Incubator

As Urza's Incubator enters, choose a creature type.
Creature spells of the chosen type cost {2} less to cast.

Mirror March

Whenever a nontoken creature you control enters, flip a coin until you lose a flip. For each flip you won, create a token that's a copy of that creature. Those tokens gain haste. Exile them at the beginning of the next end step.