msem-instigator

Mark (Whenever this creature attacks, mark target creature until end of turn.)
Whenever a marked creature you don't control blocks, Cadalon Chemist deals 1 damage to that creature.

Haste
When Challenging Pupil enters, conjure a card named Fatigue and put it on top of your library. (It's a colorless sorcery that costs {2} with “Draw a card.”)

Menace (This creature can't be blocked except by two or more creatures.)
Heroic — Whenever you cast a spell that targets Champion of Keranos, Champion of Keranos deals 2 damage to each opponent.

Trample
Deploy 3 (As this enters, you may tap any number of other creatures you control with total power 3 or more.)
When Coalition Grenadier enters deployed, it deals 4 damage to target creature you don't control.

Prowess
When Cramming Student enters, conjure ten cards named Fatigue and shuffle them into your library. (They're colorless sorceries that cost {2} and have “Draw a card.”)
Instant and sorcery spells you cast cost {1} less to cast.

Bloodprice—Reappropriate red. (You may cast this spell by sacrificing a creature and exiling two red cards from your hand and/or graveyard.)
Haste
Whenever Creed's Desperado attacks, if defending player has more cards in hand than you, exile the top card of that player's library. You may cast it as long as you control a Warrior, and you may spend mana as though it were mana of any color to cast it.

First strike (This creature deals combat damage before creatures without first strike.)

Haste
{6}{R}: Diasune Immolator deals 4 damage to target player or planeswalker.

Whenever Dissenting Vikings attacks, if you control another Warrior, it gets +1/+0 until end of turn and deals 1 damage to defending player.

Spirited (When this creature enters, you may activate one of its activated abilities without paying its cost.)
{3}{R}: When target creature dies this turn, create a 2/2 red Dragon creature token with flying and “{R}: This creature gets +1/+0 until end of turn.”

Prowess
Whenever you cast an instant or sorcery spell, if its mana value is less than or equal to Dwarven Twinslinger's power, copy that spell. You may choose new targets for the copy.

Haste
Whenever Eager Guide attacks, tap up to two target creatures you don't control.

Whenever Hatsuo attacks, if you control three or more attacking creatures, attacking creatures you control gain first strike until end of turn.
Inspired — Whenever Hatsuo becomes untapped, create a 1/1 white Warrior creature token. It gains haste and attacks this turn if able.

Haste
Other Elementals you control get +1/+0 and have haste.

Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Encrusted Sahalia desecrates a permanent, it deals 3 damage to target player.

When Expensive Tutor enters, tap target land. It doesn't untap during its controller's next untap step.

Haste
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)

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.)

{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.

When Fox of the Juniper Vale enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

{1}{B}, {T}, Remove a time counter from a permanent you control: Fretport Anarchists deals 2 damage to any target. You gain 2 life.

Haste
{W}: Fretport's Heedless gains lifelink until end of turn.
At the beginning of your end step, sacrifice Fretport's Heedless.

Improve {R} ({R}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Whenever Galdurheim Reaver attacks, it deals damage to the player or planeswalker it's attacking equal to the number of embattled creatures you control. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)