msem-instigator

Attacking creatures you control get +1/+0.

Target creature gets +1/+0 and gains first strike and haste until end of turn.

{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.

Whenever a creature you control dies, put a rot counter on Fester Swarm and you gain 1 life.
{B}{G}, Remove two or more rot counters from Fester Swarm: Create a 1/1 green Insect creature token, then put a +1/+1 counter on it for each rot counter removed this way.

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.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
{T}: Add {C}. If you're in a renaissance, add one mana of any color instead.
{3}, {T}: Scry 1.

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.

Choose one —
• Festival Sabotage deals 2 damage to any target.
• Audition for red. (Create a 1/1 Construct Actor creature token, a Warrior Role giving 3/2 and trample, or a Wizard Role giving 2/2 and prowess. Roles replace older ones.)

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

Destroy target enchantment and all other enchantments with the same name as that enchantment.
Draw a card.

Destroy target artifact and all other artifacts with the same name as that artifact.
Draw a card.

Target creature and all other creatures with the same name as that creature get +2/+2 until end of turn.
Draw a card.

Return target nonland permanent and all other permanents with the same name as that permanent to their owners' hands.
Draw a card.

Choose one —
• Target attacking creature gets +2/+2 until end of turn.
• Destroy target artifact.

Festive Servitor gets +1/+1 for each color among spells you've cast this turn.
{2}: Add one mana of any color.

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

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

Whenever a creature card is put into your graveyard from anywhere, it gains revive until the beginning of your next end step. The revive cost is equal to its mana cost increased by {1}. (Pay that card's mana cost increased by {1}, Exile that card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Whenever Fickle Feeder blocks, fateseal 1. (To fateseal 1, look at the top card of an opponent's library, then you may put it on the bottom of that player's library.)

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.

Flying
Vanishing (At the beginning of your upkeep, remove a time counter from this permanent. When the last is removed, sacrifice it.)
Ficklewing Elemental enters with a time counter on it for each card in your hand.

When Fidelity of the Pure dies, create a 1/1 green and white Elk Spirit creature token.
Revive {2}{W} ({2}{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.)