msem-instigator

Return up to one target creature to its owner's hand. Draw a card.
Tether (Then if you cast this from your hand, you may exile it tethered to a creature you control. When it dies, you may cast this from exile without paying its mana cost.)

Whenever you cast an instant or sorcery spell, Clever Infiltrator gets +2/+0 until end of turn and can't be blocked this turn.

Whenever one or more creatures you control attack, create a 1/1 white Soldier creature token that's tapped and attacking.
{3}{W}: Creatures you control get +1/+1 until end of turn.

Sacrifice Caravan Merchant: Add {R}{R}.

Motley Crew has no name while it's being cast. (It will always make first contact.)
{2}{R}: Creatures you control named Motley Crew get +1/+0 until end of turn.

Target creature you control gets +1/+1 and gains indestructible until end of turn.
Fabled {3}{W}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

Menace
When Selfserving Ghul enters, remove two counters from target permanent.

When Peddler of Commonwares enters, you may draw a card. If you do, discard a card.

This spell costs {2} less to cast if you sacrificed a Clue this turn.
Target player discards two cards.

{2}{B}, Sacrifice Determined Slayer: Exile up to three target cards from target player's graveyard. They lose that much life.

At the beginning of your upkeep, you lose 1 life, then investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Whenever you sacrifice a permanent, each opponent loses 1 life.

Create two 1/1 red Elemental creature tokens. They get +1/+0 and gain haste until end of turn.
Flashback—{1}{R}, Sacrifice a creature. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Target creature gets -4/-0 until end of turn.
Flashback {U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

When Manglehorn Hunter enters, draw a card and you lose 1 life.

When Academy Renegade enters, it deals damage to target creature you don't control equal to the number of Wizards you control.
Whenever Academy Renegade attacks, it deals damage to defending player equal to the number of Wizards you control.

When Frantic Efreetspeaker enters, you may discard a card. If you do, draw a card.
{2}, Exile Frantic Efreetspeaker from your graveyard: Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

{T}: Add {U} or {B}. You lose 1 life unless you have less life than an opponent.

{T}: Add {U} or {R}. Spend this mana only to cast an instant, sorcery, or Wizard spell.
Whenever you cast your second spell each turn, untap Innova.

Reach
Scarecrow spells you cast cost {1} less to cast.

{1}, Exile Coiling Mystic from your graveyard: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Majestic Nauticorn has first strike as long as it's attacking.
Cycling {W} ({W}, Discard this card: Draw a card.)

Destroy target creature. Creatures without flying can't block this turn.

Primal {R} (During your turn, you may cast this spell for {R} instead of playing a land.)
When Deadeye Drowner enters, it deals 2 damage to any target.

I — Exile the top card of your library face down.
II — Exile any number of cards from your hand face down.
III — Calamity of Yore deals damage to target creature or planeswalker equal to the number of cards you own in exile. Return all cards exiled with Calamity of Yore to their owners' hands.

{X}, {T}, Sacrifice Chemical Grenade: Up to X target creatures each get -1/-1 until end of turn.