msem-instigator

I, II — Scry 2.
Discovery — Whenever a land you control enters, if it doesn't have the same name as another land you control, draw a card.

When Herald of Darkness enters, destroy up to one target creature with mana value 3 or less.

At the beginning of combat on your turn, create a 1/1 red Cleric creature token with haste.
At the beginning of your end step, sacrifice each Cleric token you control unless you've cast an instant or sorcery spell this turn.

The next creature spell you cast this turn can be cast as though it had flash. When that creature enters this turn, it gains lifelink until end of turn.

{T}, Pay 1 life: Add {B} or {G}.
{1}, {T}, Sacrifice Seedy Bar: Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Target creature gets +3/-3 until end of turn.
Kindle 3—{B}{R}, Pay 3 life. ({B}{R}, Pay 3 life, Exile this card from your graveyard: Create three 1/1 colorless Elemental creature tokens. Kindle only as a sorcery.)

Whenever a land you control enters, put a +1/+1 counter on target creature you control.

Ripping Wilds enters tapped.
{T}: Add {C}.
{2}, {T}, Sacrifice Ripping Wilds: You may put up to two basic land cards from your hand onto the battlefield tapped.

Haste
Whenever Malformed Mongrel deals combat damage to a player, discard a card.

When Hardened Explorer enters, choose one —
• Destroy target artifact.
• Put a +1/+1 counter on Hardened Explorer. It gains haste.

When Diasune Irregular enters, if you control another Warrior, draw a card.

Exile target creature or planeswalker. Its controller conjures a card named Data-Point into their hand. (It's a sorcery that costs {2} with “Draw a card.”)

Colossal 3—{7}{G} (You may cast this for its colossal cost to have it enter with three +1/+1 counters; or pay {7}{G} as a sorcery: Put three +1/+1 counters on it if it has none.)
When Voracious Asvosydna's colossal ability puts one or more counters on it, you gain 5 life.

Harmony — Create a 1/1 white Bird creature token with flying.
{4}: Harmonize. (Trigger up to one harmony of one permanent you control.)

Target creature gets -3/-3 until end of turn. When that creature dies this turn, its controller loses 2 life.

When Zareen Kahroba, Shah enters, if you cast her, untap each Satrapy you control.
Whenever each Satrapy you control becomes tapped for the first time during each of your turns, untap it.

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

Flying
Whenever you aetherize, you may have Telarine Skychaser become an artifact creature until end of turn.
Crew 3 (Tap any number of creatures you control with total power 3 or greater: This Vehicle becomes an artifact creature until end of turn.)

First strike
When Sworn Cohort dies, you may search your library for a legendary card, reveal it, put it into your hand, then shuffle.

When Serum Peddler enters, you draw a card and you lose 1 life.

Syndicate Sycophant can't block.
When a creature you control scavenges Syndicate Sycophant, you may search your library for a card named Syndicate Sycophant, reveal it, put it into your hand, then shuffle.
Scavenge {2}{B} ({2}{B}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Whenever another creature enters, Masquerading Bohemian becomes a copy of that creature except it's a Noble in addition to its other types and it has this ability.

When Seeker of Far-Off Lands enters, search target opponent's library for a land card, put it onto the battlefield tapped under your control, then that player shuffles.

Flying, haste
Ride {1}{R} ({1}{R}: Transform this and attach it to target creature you control without a Steed. Ride only as a sorcery.)

Search your library for a basic land card and put it onto the battlefield, then shuffle. Create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)