msem-instigator

When Dutiful Counselor enters, adjudicate. (Create a white Aura enchantment token with enchant creature and “Sacrifice this token: Untap enchanted creature” attached to target creature.)
Whenever an Aura you control enters, you may pay {1}. If you do, target creature gets +1/+1 until end of turn.

When Elderthrone Castellan enters, you may search your library for a Plains card, reveal it, put it into your hand, then shuffle.

Empress Kogane can't attack or block.
Whenever an opponent casts a spell, you may gain life equal to that spell's mana value.

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Eos Beseecher encourages a creature, look at the top card of your library. If it's a creature card with power 2 or less, you may reveal it and put it into your hand.

Flying
Whenever Eta, Experimental Doctor attacks, you may exile target card from a graveyard. If a creature card was exiled this way, put a +1/+1 counter on Eta and you gain 2 life.

Lifelink
Whenever you draw your second card each turn, put a +1/+1 counter on Ethereal Runner.

Flying
When Ethereal Savior enters, you may return target creature card with mana value 2 or less from your graveyard to the battlefield.

Flying
Deploy 2 (As this enters, you may tap any number of other creatures you control with total power 2 or more.)
When Ethereal Shepherd enters deployed, exile target creature. That creature's controller creates a 1/1 white Spirit creature token with flying.

Flying, vigilance

When Experienced Team enters, choose one —
• Create a 4/2 white Bear creature token.
• Create a 2/4 red Snail creature token.
• Create a 2/2 white Bird creature token with flying.

Other Elemental creatures you control get +1/+0.

First strike
When Faradia's Collector enters, if an opponent controls more lands than you, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Battalion — Whenever Fellor Bloodseeker and at least two other creatures attack, Fellor Bloodseeker gains lifelink until end of turn.

{1}, {T}, Move a -1/-1 counter from another creature onto Fervent Arbiter: Exile target creature you don't control until Fervent Arbiter leaves the battlefield.

When Festival Celebrants enters, put a +1/+1 counter on each creature you control.

When Forlorn Farmhand dies, create a 1/1 colorless Spirit creature token.

Flying
Whenever a creature in Forsaken Soulherd's pack dies, look at the top card of your library. If it's a creature card with equal or lesser power, you may reveal it and put it into your hand. If you didn't put that card into your hand, you may mill it. (Two or more creatures you control with equal power are in a pack.)

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Fox of a Radiant Meadow has double strike as long as you're in a renaissance.

When Fox of the Molten Dawn enters, you may return target Aura card with mana value 3 or less from your graveyard to the battlefield attached to a permanent it could enchant.

Whenever Fox of the Mushroom Forest enters or deals combat damage to a player, its activated abilities cost {W} less to activate until your next turn.
{W}, Sacrifice Fox of the Mushroom Forest: Counter target noncreature spell unless its controller pays {2}.

When Fox of the Sunset Legion enters, create two 1/1 white Fox Spirit creature tokens.

Whenever an enchantment you control enters, put a +1/+1 counter on Freeborn Healer.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Slipstream (This creature can't be blocked as long as only creatures with slipstream are attacking.)

Flash
When Frontier Paragon enters, untap all creatures you control.

{1}{W}: Exile Furtive Witch. If you do, exile another target nonland permanent. Return both of those cards to the battlefield at the beginning of the next end step under their owners' control.