msem-instigator

Creatures you control get +2/+2 until end of turn.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

Target creature you control deals damage equal to its power to target creature or planeswalker you don't 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.”)

Enchant creature
Enchanted creature has base power and toughness 1/1 and is a Frog in addition to its other types.
When enchanted creature deals damage to a player, sacrifice Belittle.

Haste
{T}: Dragonfire Sniper deals 1 damage to target creature or planeswalker and 1 damage to that permanent's controller.

Trample, haste
Whenever Lisseria, General of Kanaa attacks, you may exchange its power with the power of target creature defending player controls until end of turn.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Kalime Charger enters, you may have another target creature you control gain trample until end of turn.

{1}, {T}, Move a -1/-1 counter from another creature onto Zealous Bloodletter: Proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Greenheart Den enters tapped.
{T}: Add {G}.
{G}, {T}: Target creature you control gets +1/+1 until end of turn. Activate only as a sorcery and only if you control a green creature.

Draw a card, then copy target activated or triggered ability you don't control. You may choose new targets for the copy.
Exile Confirm Hypothesis.

Target creature you control gains trample until end of turn. Whenever that creature deals damage to a player this turn, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Each opponent loses 2 life. Scry 1.
Showcase {3}{B} (Then if you cast this for its showcase cost, create a 1/1 red Bard creature token that can't block and exile this. Whenever it attacks, you may cast a free copy of this.)

When Seafloor Cache enters and when you sacrifice it, create a Treasure token.
{1}{R}, Sacrifice Seafloor Cache: Draw a card.
Cycling {2} ({2}, Discard this card: Draw a card.)

Meletian Trireme can't be blocked by creatures with power 2 or less.
Whenever Meletian Trireme enters or deals combat damage to a player or planeswalker, scry 1, then draw a card.
Crew 2 (Tap any number of creatures you control with total power 2 or greater: This Vehicle becomes an artifact creature until end of turn.)

At the beginning of your upkeep, you may pay {G}. If you do, you may put a +1/+1 counter on target creature you control and you gain 2 life.

{2}{U}: Return Windcaller Capuchin to its owner's hand.

Trial 2 (As you cast this spell, an opponent of your choice may pay 2 life. If they don't, they fail the trial.)
When Nascent Adversary enters, if the trial was failed, it gains haste and first strike until end of turn.

Revive {3}{B} ({3}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

When Warrior's Perspective enters, invigorate 1. (Choose a creature with the least power among creatures you control and put a +1/+1 counter on it.)
Whenever a creature you control with a +1/+1 counter on it becomes tapped, you may draw a card. If you do, discard a card.

As long as Armed Vendor is enchanted or equipped, it gets +1/+0 and has menace.

Deathtouch
Menagerie — When Sting-Hopper enters, if there are five or more creature types among creatures you control, target player reveals their hand. You choose a creature card from it. That player discards that card.

Look at the top four cards of your library. You may reveal a creature or land card from among them and put it into your hand. Put the rest into your graveyard.

Whenever an artifact or enchantment you control enters, you may detain target nonland permanent. (Until your next turn, that permanent can't attack or block and its activated abilities can't be activated.)

At the beginning of your upkeep, draw a card.
At the beginning of your end step, discard a card.

Target player discards two cards and loses 2 life. Scry 2. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

At the beginning of your upkeep, if there are no noncreature cards in your graveyard, you may return target creature card from your graveyard to the battlefield.