msem-instigator

When Ethereal Spellmaster enters, if it was cast, you may search your library for an instant or sorcery card with mana value 3 or less and cast it without paying its mana cost. If you do, shuffle your library. (If it has X in its mana cost, X is 0.)

Defender
When Ethereal Threshold enters, if it was cast, exile target artifact or creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.

When Ethersworn Elite enters, you gain 2 life and create two 1/1 blue Thopter artifact creature tokens with flying.
Cycling {2} ({2}, Discard this card: Draw a card.)

Whenever Evaldi's Muse or another nontoken creature you control enters, you gain 2 life.
When Evaldi's Muse leaves the battlefield, create two 1/1 green and blue Elf creature tokens.

Lifelink
Mirage {1}{W} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Eve's Spiritstalker attacks or mentors a creature, you lose 1 life.

When Evershedder dies, you may put it on the bottom of its owner's library.
Morph {2}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

{T}: Draw a card, then discard a card.
Whenever you cast an instant or sorcery spell, untap Exchange Scholar.

Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Exemplar of Disdain desecrates a permanent, target creature you don't control gets -3/-3 until end of turn.

Vigilance
{G}, {T}: Exile up to three target cards from graveyards. If two or more of those cards share a card type, create a 1/1 colorless Servo artifact creature token.

{1}, {T}, Exile a land card from your graveyard: Add two mana in any combination of colors.
{B}{G}, {T}, Discard a card: Nourish 2. (To nourish 2, either put two +1/+1 counters on this creature or create two 1/1 white Citizen creature tokens.)

Flash
When Expedition Duo enters, if you cast an Adventure spell or a permanent you controlled explored this turn, draw a card.

Cycling {3} ({3}, Discard this card: Draw a card.)

Explosion Fanatic can't attack unless an opponent was dealt damage this turn.

As Extinction Specialist enters, note two creature types.
Whenever Extinction Specialist enters or attacks, choose one of the noted creature types. Creatures you don't control of the chosen type get -1/-1 until end of turn.

Reach
When Extolled Arachstruct enters, mill two cards. When you do, choose one —
• Each opponent sacrifices a creature with power less than the number of cards in your graveyard.
• Each opponent sacrifices a creature with power greater than the number of cards in your graveyard.

Stampede — Whenever Exuberant Hunter and a creature with greater power attack, draw a card.

{2}, {T}: Tap target creature. This ability costs {2} less to activate if you control an enchantment.

Vigilance
Players can't untap more than two lands during their untap steps.

Unveil {3}{G}{W} ({3}{G}{W}: Transform this. Unveil only as a sorcery.)

Gestalt (When this or another creature enters under your control, you may merge it with the one in play, keeping counters and attachments. They become the permanent on top plus all abilities from under it.)
Vigilance, lifelink
Whenever an opponent casts a spell, this permanent phases out until end of turn. (Treat it and anything attached to it as though they don't exist until end of turn.)

Whenever a creature blocks or becomes blocked by Faceless Virtue, that creature loses all abilities until end of combat.

When Fae-Blessed Attendant enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Whenever you sacrifice a Clue, untap target permanent.

Fahrib's Tongue can't be blocked by creatures with two or more creature types.
Whenever Fahrib's Tongue deals combat damage to a player, that player loses 1 life for each creature that dealt damage to them this turn.

Whenever Failed Martyr attacks, each other attacking creature gets +1/+0 until end of turn.
Attain {4}{W} ({4}{W}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)