msem-instigator

Stampede — Whenever Etlan High Priest and a creature with greater power attack, Etlan High Priest gets +1/+1 until end of turn. Then you gain 1 life and scry 1.

At the beginning of combat on your turn, if you control a creature with power greater than Ever-Gnawing Rat's, put a +1/+1 counter on Ever-Gnawing Rat.

{T}: Create an X/X green Elemental creature token, where X is Evoker of the Ancient Form's power.

When Evolving Elemental enters, scry 3, then reveal the top card of your library. Put a number of +1/+1 counters on Evolving Elemental equal to that card's mana value.

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

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

Vigilance
When Expendable Victim dies, create a 1/1 colorless Construct Actor creature token.

Whenever another Avatar you control enters, upgrade it and Experienced Mentor. (Give each one of the listed counters it doesn't already have. Upgrades are independent.)
• +1/+1
• First strike
• Vigilance

Whenever you cast your second spell each turn, Expressive Performer deals 1 damage to each opponent.
{3}{R}, {T}, Exert Expressive Performer: It deals 2 damage to each player. (An exerted creature won't untap during your next untap step.)

Eureka! (At the beginning of each end step, you get a research counter if you cast a spell this turn. Then if you have eight or more research counters, remove them and create a Masterpiece token of your choice.)
At the beginning of your first end step each turn, you get an additional end step after this step.

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

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 Informant can't be blocked by creatures with greater power.
Whenever one or more creatures you control deal damage to an opponent, put a +1/+1 counter on Fahrib Informant.

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 you gain life, put a +1/+1 counter on Faithful Acolyte.
Faithful Acolyte has lifelink as long as it has four or more +1/+1 counters on it.

Whenever Fallacy's Channeler becomes untapped, each player sacrifices a creature.
{T}, Pay 1 life: Fallacy's Channeler deals 1 damage to any target.

When False-Cure Smuggler enters, put a -1/-1 counter on another target creature.
{1}{U}, Sacrifice a creature: Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Whenever you put one or more -1/-1 counters on one or more creatures, each opponent loses 1 life and you gain 1 life.

Flying
Other creatures you control with flying get +1/+1.

When Far-Realm Guardian enters, create a green Aura enchantment token named Wild Bounty attached to target creature. The token has enchant creature and “Enchanted creature gets +1/+1 and has ward {2}.”

Whenever one or more other creatures you control enter, you gain 1 life. If at least one of those creatures was a Cleric, you gain 2 life instead.
As long as you have at least 8 life more than your starting life total, other Clerics you control get +1/+1.

{1}{W}, {T}: Aetherize target creature you control. (To aetherize, create a token that's a copy of it, then exile that token.)

Enchantment spells you cast cost {1} less to cast.

Vigilance
Whenever Fate Tracer attacks, rediscover a creature or enchantment card X times, where X is Fate Tracer's power. (Repeat this process X times: Look at the top card of your library. You may reveal it and put it into your hand if it's a creature or enchantment card. Otherwise, put it back or into your graveyard.)

Whenever Fated Mariner attacks, forebode. (Create a tapped colorless Omen artifact token with “{T}, Discard a card, Sacrifice this artifact: Draw a card.”)
{1}{U}: Fated Mariner can't be blocked this turn.