msem-instigator

Target creature fights another target creature. (Each deals damage equal to its power to the other.)

{1}, Sacrifice Curious Fossil: Scry 2.
{2}{U}: Return Curious Fossil from your graveyard to the battlefield transformed. Activate only during your turn.

At the beginning of your upkeep, if Blade of Ancestors isn't attached to a creature, create a 1/1 white Soldier creature token, then attach Blade of Ancestors to it.
Equipped creature gets +1/+1.
Equip {2}

When Osseous Augur enters, target creature an opponent controls gets -1/-1 until end of turn. If that creature's controller is cursed, that creature gets -3/-3 until end of turn instead.

Pressure—{4}{U}{B}, Sacrifice two creatures. (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
Whenever Oryxyth enters or attacks, create an X/X black Horror creature token, where X is the number of cards in your graveyard.
{U}{B}, Sacrifice another creature: Gain control of target creature with power less than the sacrificed creature's power.

Counter target spell unless its controller pays {2}.
Wanderlust — If that spell has mana value 2 or less and you control four or more differently named lands, counter that spell.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Noncreature spells you cast cost {1} less to cast. This effect can't reduce the amount of mana a spell costs to cast to less than one mana.

When Veiled Transmuter enters, you may cast an instant or sorcery card with mana value 2 or less from your hand without paying its mana cost.
Magecraft — Whenever you cast or copy an instant or sorcery spell, create a 2/2 blue Reflection creature token.

You may have Terracotta Legion enter as a copy of any creature with mana value 1 or less you control, except it's an artifact in addition to its other types.

Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)
Whenever Irreguleopard deals combat damage to a player, permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

First strike, vigilance
Partner with Commander Hyctaleon (When this creature enters, target player may put Commander Hyctaleon into their hand from their library, then shuffle.)
At the beginning of your upkeep, you may search your library for a Soldier card, reveal it, put it into your hand, then shuffle.

Glitch {U} (Remove one [restriction] for each time you pay the glitch cost.)
Counter target [noncreature] spell [unless its controller pays {2}].

Exile target creature you control, then return it to the battlefield under its owner's control.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

Move all counters from target creature onto another target creature.

Return target permanent card from your graveyard to your hand. If it's an enchantment card, create a 2/2 black Zombie creature token.

Target creature gets +1/+0 until end of turn. Add {R}.

Choose one—
• Return target creature to its owner's hand.
• Target creature gets +2/+0 and gains first strike until end of turn.
• Draw two cards, then discard a card at random.

Another target player reveals their hand. You may choose a nonland card from it. That player discards that card.
Fuse (You may cast one or both halves of this card from your hand.)

Trial 3 (As you cast this spell, an opponent of your choice may pay 3 life. If they don't, they fail the trial.)
When Inspired Trialmaker enters, if the trial was failed, add {R}{W}{B}.

Flying
When Bogsnatcher Drake enters, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Prowess
When Maktali Visionary enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

({T}: Add {W} or {U}.)
Whenever Sedate Tundra becomes tapped, you lose 1 life unless you control two or more basic lands.

Reveal the top four cards of your library. You may put a creature or Revelation card from among them into your hand. Put the rest into your graveyard.

Reverent Flame deals 3 damage to target creature. Create three Idol tokens. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

{T}, Sacrifice a land: Destroy target land.