msem-instigator

Each player chooses a legendary permanent from among the nonland permanents they control, then sacrifices the rest.

As an additional cost to cast this spell, pay {4} or sacrifice a creature.
Target creature gets -13/-13 until end of turn. If that creature would die this turn, exile it instead.

When Final Form enters, your life total becomes 20.
At the beginning of your upkeep, destroy up to one target creature. You draw X cards and you lose X life, where X is its power.

Choose one —
• Draw seven cards.
• End the turn. (Exile all spells and abilities, including this. The player whose turn it is discards down to their max hand size. Damage wears off, and “this turn” and “until end of turn” effects end.)

Reprise {3}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)
Scry 3, then draw a card.

Final Struggle deals 3 damage to target creature. When that creature dies this turn, exile it and create a 3/3 red Shark enchantment creature token.

When Final Symphony enters, exile another target nonland permanent until Final Symphony leaves the battlefield.
When Final Symphony leaves the battlefield, draw a card.

Destroy all creatures that aren't enchanted.

Finale of Cinders deals 2 damage to any target. For each instant and sorcery card in your graveyard, you may pay {R}. Whenever you do, Finale of Cinders deals 2 damage to any target.

Choose X —
• Return target spell to its owner's hand.
• Scry 3.
• Draw a card.

Exile the top card of your library. You may cast it. (Then exile this card. You may play the land later from exile.)

Create two 1/1 Insect creature tokens that are all colors.
Create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

Enchant artifact
Enchanted artifact is an Equipment and has “Equipped creature gets +2/+0” and equip {0}.

Finish the Job deals 5 damage to target creature that was dealt damage this turn. If that creature would die this turn, exile it instead.

Rouse 1. Finishing Blow deals X damage to any target, where X is the greatest power among creatures you control. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)

Destroy target creature if it was dealt damage this turn.

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Fire from Above deals 2 damage to target opponent and each creature with flying that player controls.

Exile the top three cards of your library. Until the end of your next turn, you may play those cards.

This spell can't be countered.
Firebloom deals 3 damage to target creature or planeswalker.

Firebolt deals 2 damage to any target.
Flashback {4}{R} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Choose target creature you control, then choose two —
• Put a +1/+1 counter on it.
• Put a first strike counter on it.
• Put a trample counter on it.

Whenever Firefall Praetorians attacks, exile the top card of your library then copy it. You may play the copy and/or the exiled card.

At the beginning of each combat, you may have Firefish Conjurer deal 3 damage to target creature you control. If you do, Firefish Conjurer gets +2/+0 and gains flying until end of turn.

Whenever Fireheart Centaur attacks, you may pay {2}{R}. If you do, it gets +1/+0 until end of turn for each Centaur you control.