msem-instigator

Cesspool Scrapper can't block.
{5}{U}, Exile Cesspool Scrapper from your graveyard: Draw two cards.

{B}, Sacrifice another creature: Deranged Apothecary gains indestructible until end of turn.

Concord — {T}: Tap target nonland permanent. Activate only if there are four or more card types among permanents you control.

Whenever you upgrade another creature you control, upgrade Lelin, the Wise. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Flying
• First strike
• Vigilance
• Lifelink
• Hexproof

Search your library for a permanent card that could produce {G}, reveal it, put it into your hand, then shuffle.

Frenzy 1 (Whenever this creature attacks and isn't blocked, it gets +1/+0 until end of turn.)

({T}: Add {U} or {B}.)
Sodden Cavern enters tapped.

Until end of turn, target creature you control gets +1/+0 and gains “{T}: This creature deals damage equal to its power to up to one target creature.”

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Whenever a Demon you control enters, put a +1/+1 counter on Tzelin.
{2}{B}: Sacrifice Tzelin. If you do, each opponent loses life equal to Tzelin's power. If you're in a renaissance, also draw that many cards.

Distribute three +1/+1 counters among one, two, or three target creatures you control.

Prowess
{1}{R}: Until end of turn, if an instant, sorcery, or Dragon source you control would deal damage to a permanent or player, it deals that much damage plus 1 to that permanent or player instead. Activate only once each turn.

At the beginning of combat on your turn, you may have target artifact you control become a 3/3 artifact creature until end of turn. If you do, it and Field Engineer attack this turn if able.

Flying
When Cadre Hawk enters, you may search your library and/or graveyard for a card named Cadre Hawk, reveal it, and put it into your hand. If you searched a library this way, shuffle.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, you may switch Master of Tranquility's power and toughness until end of turn.

Sabotage — Whenever an opponent or permanent an opponent controls becomes the target of a spell you control, Artisan of Brutality gets +2/+0 and gains first strike until end of turn.

Remove all counters from target permanent with counters. If it's a creature or enchantment, destroy it.

Whenever Poised Koi attacks or blocks, look at the top two cards of your library, put any of them into your graveyard, then the rest back on top in any order.

Prowess, haste
Mirage {R} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

When Kaneh Scribe enters, amass Soldiers 2. (Put two +1/+1 counters on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Flying, lifelink
Menagerie — When Gloomhollow Fluffpuff enters, if there are five or more creature types among creatures you control, you may search your library for a card named Gloomhollow Fluffpuff, reveal it, put it into your hand, then shuffle.

(Choose only one work as a sorcery to add its ability.)
When Celebrations of Ferocity enters, add {R}{G}. Spend this mana only to cast creature spells.
{4}{R}{R}: Hao'Tai's Wake
At the beginning of combat on your turn, target creature you control becomes a 4/4 red Dragon with flying until end of turn.
{1}{G}: Portrait of Qiyan
Creatures you control enter with an additional +1/+1 counter on them.

First strike, haste
Whenever you cast an instant or sorcery spell, Flamedaunt Courier gets +2/+0 until end of turn.

Haste
{T}, Discard a card: Flip a coin. If you win the flip, draw two cards. Otherwise, you may pay {R}. If you do, repeat this process.

You gain hexproof until end of turn.
Prevent all damage that would be dealt to you this turn.

Scry 2, then draw a card. (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.)
Foresee — As you draw Read the Clouds, you may reveal it and pay {1}{U}. When you do, scry 2, then draw a card.