msem-instigator

Target creature gets +1/+5 until end of turn.
Draw a card.

Trample
Whenever a creature you control with trample is dealt damage, put a +1/+1 counter on it. (It must survive the damage to get the counter.)

Whenever you cast an instant or sorcery spell, tap target creature an opponent controls.

Flying
When Goldnight Seraph enters, it deals X damage to up to one target creature or planeswalker and you gain X life, where X is the number of artifacts you control.

When Leech-Ridden Corpse dies, each opponent loses 1 life and you gain 1 life.

Whenever a creature enters under an opponent's control, you may have that player lose 1 life.
Unveil {2}{B}{R} ({2}{B}{R}: Transform this. Unveil only as a sorcery.)

Flying, vigilance
Orzhov Benefactor can't attack or block unless you pay {1} for each debt counter on it.
At the beginning of your upkeep, put a debt counter on Orzhov Benefactor.
{2}: Remove a debt counter from Orzhov Benefactor.

Whenever War Priest of Bahet deals combat damage to a player, purge. (Exile two cards that share a type from graveyards. If you do, draw a card.)

You may cast up to two target instant and/or sorcery cards from your graveyard this turn. If a spell cast this way would be put into your graveyard, exile it instead.

{2}{B}: Return Sanitarium Skeleton from your graveyard to your hand.

Whenever a player casts an instant or sorcery spell that targets only one target or activates an ability that targets only one target, copy that spell or ability for each other target it could target. Each copy targets a different one of those targets. (A spell or ability can't target itself.)

When Mythos Scribe enters, you may return target storied card from your graveyard to your hand. (Enchantments and legendary permanents are storied.)

You may activate Boxue and Ma'Long's loyalty abilities an additional time if you've cast two or more spells this turn.
[+1]: Scry 2.
[–2]: Exile the top two cards of your library. You may play one of them this turn. When you do, put the other card into your hand.
[–6]: Whenever you cast a spell this turn, copy it. You may choose new targets for the copy.

Haste
Sacrifice another creature: Bygone Aristocrat gains indestructible until end of turn.

Return Portal to the Unknown to its owner's hand: Add {U}{U}{U}. The next card you cast this turn can be cast as though it had flash.

Menace
Jara Champion can only attack or block alone.
Whenever one or more players lose life for the first time each turn, put a +1/+1 counter on Jara Champion.

Enchant creature you control
Enchanted creature has lifelink.
When Phantasmal Possession enters, exile target creature an opponent controls until Phantasmal Possession leaves the battlefield.

Destroy target attacking creature.

I, II — Whenever a creature you control attacks alone this turn, put a +1/+1 counter on it.
III — Whenever a creature you control attacks alone this turn, it gains double strike and lifelink until end of turn.

Gain control of target nonland permanent an opponent controls. Its owner reveals cards from the top of their library until they reveal a card that shares a type with that permanent, then puts it onto the battlefield and shuffles.

You gain 4 life. Then if you have more life than an opponent, draw a card.

Flash
Enchant artifact or creature
Enchanted permanent is an artifact with “{T}: Draw a card, then discard a card” and loses all other card types and abilities.

When Suspect Concoctions enters, put a +1/+1 counter on target creature.
{4}, Sacrifice Suspect Concoctions: Put two +1/+1 counters on target creature.

[+1]: Haide Bankbuster deals 2 damage divided as you choose among one or two targets.
[+1]: Draw two cards unless any player has Haide Bankbuster deal 3 damage to them.
[–9]: Until end of turn, gain control of all permanents target player controls and they gain haste. Untap those permanents.

When Crystalline Golem enters, choose a color. You gain 1 life for each permanent of that color you control.