msem-instigator

[+1]: Augur. (Look at the top card of your library. You may sacrifice a creature to put it into your hand. Otherwise, put it back or put it into your graveyard.)
[–X]: Exile target card in your graveyard with mana value X. Copy it. You may cast the copy without paying its mana cost.
[–6]: You get an emblem with “Whenever a creature you control dies, search your library for a creature card, reveal it, and put it into your hand, then shuffle.”

Deathtouch, protection from legendary
Vielle, Undercity Wayfarer has all loyalty abilities of permanents on the battlefield that cost +1, +0, or -1. (Before cost changes. Add or remove loyalty counters from Vielle to pay their loyalty costs.)

When Wayward Bloodseeker enters, put a +1/+1 counter on up to one target creature you control. When you do, Wayward Bloodseeker deals damage to any target equal to the number of permanents you control with counters on them.

When Wild Entourage enters, create two 1/1 colorless Construct Actor creature tokens.
{4}{G}: Wild Entourage gets +2/+2 and gains trample until end of turn.

Whenever Witchfinder Artur enters or attacks, each opponent mills two cards and loses 2 life.
Whenever you cast an instant or sorcery spell, you may exile target instant or sorcery card with mana value less than that spell's mana value from an opponent's graveyard. If you do, cast a copy of the exiled card without paying its mana cost.

Untap target creature you control. It gets +1/+4 and gains hexproof and reach until end of turn.

{R}: Xiyue Dragondancer gets +1/+0 until end of turn.
Whenever you cycle Xiyue Dragondancer or it attacks, create a Treasure token.
Basic landcycling {1}{R} ({1}{R}, Discard this card: Search your library for a basic land card, reveal it, and put it into your hand, then shuffle.)

Whenever one or more creatures you control deal combat damage to a player or planeswalker, put a +1/+1 counter on target creature you control.

{1}{G}: Create a 1/1 colorless Construct artifact creature token.
{2}{G}{G}: Target creature you control becomes 4/4. (This lasts indefinitely.)
{4}{G}{G}{G}{G}: Put four +1/+1 counters on each creature you control with power 4 or greater.

{T}, Pay 1 life: Add one mana of any color.

Flying, vigilance
If a nonland permanent entering the battlefield would cause a triggered ability of a permanent you control to trigger, you may have that ability trigger an additional time. If you do, each opponent copies that ability and may choose new targets for the copies.

Until end of turn, creatures you control get +1/+1 and creatures your opponents control get -1/-1.

Flying, ward {2}
Whenever you cast a noncreature spell, choose up to one target creature. If that spell's mana value is greater than that creature's power, put +1/+1 counters on it equal to the difference.

{T}, Pay 1 life, Sacrifice Abbey of Masquerades: Create a tapped Plains token, Island token, Swamp token, Mountain token, or Forest token.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Counter target activated ability from a nonland source. (Mana abilities can't be targeted.)
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

[+1]: Create a 1/1 black Faerie creature token with flying and a 2/2 white Spirit Noble creature token with lifelink.
[–X]: Target creature gets -X/-X until end of turn. Its controller loses X life.
[–7]: You get an emblem with “Whenever a permanent you control enters, you may have it gain flying and vigilance and become a 4/4 Angel creature in addition to its other types.” (This effect lasts indefinitely.)

Haste
Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)

When Adept of Rations enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Tokens you control have “{2}, {T}, Sacrifice this token: You gain 3 life.”

Prowess
When Adept of Signals enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Tokens you control have “{2}, {T}: Sacrifice this token: Draw a card.”

Lifelink
When Adept of Transfusions enters, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
Tokens you control have “{1}, {T}, Discard a card, Sacrifice this token: Draw a card.”

Target creature you control fights target creature you don't control. You may discard a card. If you do, draw a card.

Creatures you control get +1/+1 until end of turn.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

When Ageless Ascetic enters, return up to one target instant or sorcery card from your graveyard to your hand.

Untap target creature. It gets +1/+1 for each token you control until end of turn.

Choose one—
• Target creature gets -3/-3 until end of turn.
• All creatures get -1/-1 until end of turn.