msem-instigator

Flying
Whenever an opponent draws a card except for the first time each turn, create a 1/1 blue Elemental creature token with flying.
Foresight — Whenever you draw your second card each turn, creatures you control get +1/+1 until end of turn.

When Acolyte of Griselbrand dies, you draw a card and you lose 1 life.
Foreshadow {4}{B} (You may cast this spell for its foreshadow cost. If you do, also trigger its “dies” abilities when it enters.)

{T}: Add {C}. You gain 1 life.
Pristine Frame gets +2/+2 and has flying as long as you have 25 or more life.

When Stalwart Physicker enters, you may remove a -1/-1 counter from target creature.

Enchant creature you control
When Erebos's Benefaction enters, scry 2.
Enchanted creature gets +2/+2 and has menace.

Face-down creatures you control get +1/+1 and have flying.

Eternal Oak gets +1/+1 for each creature you control.
Whenever a nontoken creature you control dies, create a 1/1 green Saproling creature token.

Noncreature permanents you control become 2/2 red creatures in addition to their other types until end of turn.
Fuse (You may cast one or both halves of this card from your hand.)

When Percy's Perfect World enters, search your library for a legendary white card, reveal it, put it into your hand, then shuffle.
If an effect would create one or more creature tokens under your control, it creates twice that many of those tokens instead.

When Remnant of Lost Times enters, scry 1.
{2}, Sacrifice Remnant of Lost Times: Draw a card.

[+2]: Exile the top two cards of your library. You may put a permanent card from among them into your hand.
[–3]: Create Salim, a legendary 3/3 green and white Cat creature token with vigilance, trample, and indestructible.
[–3]: You get an emblem with “Whenever a creature you control enters, that creature gets +2/+2 and gains haste until end of turn.”

Prowess
Whenever you cast a noncreature spell, you may choose target permanent with one or more time counters on it, then put a time counter on it or remove a time counter from it.

Target opponent sacrifices a creature.
Rerun (If you cast this from your hand, exile it as it resolves. Whenever a creature you control dies, you may cast this card from exile without paying its mana cost.)

[+1]: Scry 2. Whenever one or more creatures you control deal combat damage to a player this turn, draw a card.
[–2]: Create a token that's a copy of target creature you control, except the token is 4/4 and has vigilance.
[–7]: You get an emblem with “At the beginning of your draw step, draw two additional cards” and “Creatures you control get +1/+1 for each card you've drawn this turn.”

Menace
You may spend mana as though it were mana of any color to cast double-faced spells or activate abilities of double-faced sources.
Once during each of your turns, you may cast a double-faced spell you own from outside the game.

Whenever another Goblin you control attacks, you may pay {1}. If you do, it gets +1/+0 until end of turn.

Whenever an opponent casts a noncreature spell, put a +1/+1 counter on target creature you control.

Draw a card.
Civilized — Instead draw two cards if you control an artifact, a creature, and an enchantment.

When Arpechian Stag enters, create a 3/3 red Elk creature token with haste, a 3/3 green Elk creature token with trample, and a 3/3 white Elk creature token with vigilance.

Enchant creature
When Til Death enters, exile target creature an opponent controls other than enchanted creature until Til Death leaves the battlefield.
Enchanted creature has defender.

Improve {1} ({1}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
At the beginning of combat on your turn, target creature you control with mana value 3 or less can't be blocked this turn. If Streetwise Investigator has two or more counters on it, that creature gains vigilance until end of turn.

{2}{R}: Ruthless Mastiff gets +3/+0 until end of turn.

Aetherize each permanent you control. Exile Beneath the Horizon. (To aetherize a permanent, create a token that's a copy of it, then exile that token.)

Saga spells you cast cost {1} less to cast.

{T}: Add {G}. Spend this mana only to cast a creature spell or activate an ability of a creature.
At the beginning of combat on your turn, if you control a creature with power 4 or greater, Vassal of the Wild gets +2/+1 and gains vigilance until end of turn.