msem-instigator

Destroy target creature with power 4 or greater.
Create two Idol tokens. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Each player chooses a creature with the least power among creatures they control. Then destroy the rest.

You gain 3 life. Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Destroy target creature with flying.

Equipment spells you cast cost {1} less to cast.
Armed — As long as Fellor Armorsmith is equipped, equip abilities you control cost {1} less to activate.

First strike

Haste
{1}{W}: Fellor Heartstriker gains lifelink until end of turn.

When Fellor Ironborn enters, you may return target artifact card from your graveyard to the battlefield. If it's an Equipment, you may attach it to target creature you control.

Battalion — Whenever Fellor Raider and at least two other creatures attack, Fellor Raider deals 2 damage to defending player.

Trample
Whenever Fellor Razer deals combat damage to a player, that player sacrifices a land.

Haste
Battalion — Whenever Fellor Tactician and at least two other creatures attack, creatures you control get +1/+1 until end of turn.

Harmony — Target creature you control gets +1/+0 and gains first strike until end of turn.
When Fellor War-Skald enters, harmonize. (Trigger up to one harmony of a permanent you control.)

Lifelink
Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Fellow Traveler enters deployed, you and target opponent each draw two cards.

{R}{W}, {T}: Femourri Archer deals damage equal to its power to any target. You gain that much life.

Menace
As long as you control exactly one other creature, that creature gets +1/+1 and has menace.

Double strike
When Fencing Tutor enters, create a 0/1 white Soldier creature token with double strike.

[+1]: Until your next turn, whenever up to one target permanent deals damage to another permanent or player, it deals that much damage to itself.
[–X]: When you next cast a noncreature spell with mana value X or less this turn, copy it. You may choose new targets for the copy.
[–2]: Create an X/X blue Spirit creature token, where X is the number of colors of mana you've spent to cast spells this turn.

Menace
When Fenhauler Gang enters, each player mills three cards.
Whenever Fenhauler Gang deals combat damage to a player, return up to one target creature or land card from your graveyard to your hand.

Fennec Fostress gets +1/+0 for each Aura you control.

Once each turn, you may cast a creature you control from the battlefield.
(You can cast its Adventure this way.)

{R/G}: Fento, Nova Crusader gains haste and trample until end of turn.
Whenever Fento, Nova Crusader attacks, you may put a creature card from your hand onto the battlefield tapped and attacking. If you do, sacrifice that creature at the beginning of the next end step.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

Equipped creature gets +3/+0.
Whenever a creature you control attacks and isn't blocked, you may pay {4}. If you do, attach Feral Cleaver to that creature.
Equip {3}

{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.

Colossal 3—{4}{R}{G} (You may cast this for its colossal cost to have it enter with three +1/+1 counters; or pay {4}{R}{G} as a sorcery: Put three +1/+1 counters on it if it has none.)
Each creature you control with a counter on it can't be blocked by more than one creature.