msem-instigator

{1}{R}{G}: Feral Exemplar gets +2/+2 until end of turn. Activate only once each turn.
Ferocious — Whenever a creature you control with power 4 or greater attacks, that creature gets +X/+X until end of turn, where X is its power.

Wanderlust — Feral Ornithax gets +2/+2 and has trample as long as you control four or more differently named lands.

When Feralborn Druid enters, create two 2/2 green Wolf creature tokens.
Feralborn Druid gets +1/+1 for each Wolf you control.

When Ferocity of the Redeemed enters, return up to two target creature cards with mana value 1 or less from your graveyard to the battlefield.
Revive {2}{W}{W} ({2}{W}{W}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

{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.

Chosen one ({W}{U}{B}{R}{G}: Transform this permanent.)
Whenever Fervent Ensign attacks, add {R} at the beginning of your next main phase.

Attacking creatures you control get +1/+0.

{2}{R}{R}, Exile an instant or sorcery card from your graveyard: Fervid Dragonheart gets +1/+2, gains flying, and becomes a Dragon until end of turn.

Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

When Festering Waif enters, each opponent mills two cards.
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.)

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

Inspired — Whenever Festival Decorator becomes untapped, draw a card.

When Festival Rioters enters, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”
{1}{R}: Festival Rioters gets +2/+0 until end of turn.

Harmony — Create a 1/1 white Bird creature token with flying.
{4}: Harmonize. (Trigger up to one harmony of one permanent you control.)

{B}: Fetid Nibbler gains deathtouch until end of turn.

When Feverish Noble dies, you draw two cards and you lose 2 life.

Vanishing 3 (This creature enters with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
When Fickleflame Summon enters or leaves the battlefield, draw a card, then discard a card.

When Field Technician enters, you may search your library for an artifact card, reveal it, then shuffle and put that card on top of it.
Artifact creatures you control get +1/+1.

You may play lands from your graveyard.
Whenever a land you control enters, create a 1/1 white Peasant creature token.

Whenever you cast a noncreature spell, judge target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

Flash
When Fiery Truthseeker enters, you may cast target instant or sorcery card with mana value 3 or less from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

{R}, Sacrifice Firebelly Toad: It deals 3 damage to target player or planeswalker.

First strike, haste
Other creatures you control with flash or haste have first strike.

First strike, vigilance
Spells that your opponents cast that target First Wave Explorer cost {2} more to cast.

When Flame Ascetic enters, you may exile up to one instant card and up to one sorcery card from your graveyard. Put a +1/+1 counter on Flame Ascetic for each card exiled this way.