msem-instigator

Ominous Lightning deals 3 damage to target creature. Scry 2.

Whenever you draw a card, put a foreshadow counter on Ominous Seas.
Remove eight foreshadow counters from Ominous Seas: Create an 8/8 blue Kraken creature token.
Cycling {2} ({2}, Discard this card: Draw a card.)

Target creature gets -2/-2 until end of turn.
{3}{B}{B}, Exile Ominous Wind from your graveyard: Each creature gets -2/-2 until end of turn. Activate only as a sorcery.

Enchant creature
Enchanted creature doesn't untap during its controller's untap step.

Exile target creature or enchantment you control, then return that card to the battlefield under your control.
You may cast On Repeat from your graveyard any time you could cast a sorcery by discarding a land card in addition to paying its other costs.

Proliferate (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)
Scry 2, then draw a card.

Exile target creature you control, then return that card to the battlefield under its owner's control. 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.”)

This spell costs {R} less to cast if it targets a white or blue permanent.
Once Scarred deals 4 damage to target creature or planeswalker.

Destroy target monocolored creature.
Augmented — If you've spent {W}{U}{B}{R}{G} to cast spells this turn, return that card to the battlefield under your control.

Choose one or both —
• Put a +1/+1 counter on each of up to two target creatures.
• Put a +1/+1 counter on up to one target Elemental and up to one target Soldier.

Reprise {3}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)
Create a Treasure token. You draw cards equal to the number of tokens created by this spell.

Enchant creature
Enchanted creature gets +2/+2 and has flying.

Prowess
When One of Purpose enters, if you cast it, create a Function token with “If you cast this spell from your hand, exile it. You may cast it from exile until the end of your next turn.” (It's an enchantment. As you cast an instant or sorcery spell, sacrifice any number of Functions to add their effects to that spell.)

Vanguard — Whenever a creature you control attacks alone, put a +1/+1 counter on it.

Colorless creatures you control get +1/+1.

Until end of turn, target creature gets +X/+X and can only be blocked by X or more creatures.

Target player mills seven cards.
Inscribe {3}{U}{B} ({3}{U}{B}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Whenever you draw a card, put a +1/+1 counter on Ontarachie Curio.
{T}, Remove a +1/+1 counter from Ontarachie Curio: Create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”
{1}{G}: Ontarachie Curio becomes a green 2/1 Dryad creature until end of turn. (It's no longer an artifact.)

When Ontarachie Emissary leaves the battlefield, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

If you would germinate, instead create a 1/1 green Saproling creature token, then put a +1/+1 counter on a creature you control.
{2}{W}{W}: Germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Search your library for a land card, reveal it, then shuffle and put that card on top. (Then exile this card. You may play the land later from exile.)

At the beginning of your upkeep, each player conjures a card named Data-Point into their hand. (It's a sorcery that costs {2} with “Draw a card.”)

Destroy target artifact. Scry 1.

At the beginning of your upkeep, reveal the bottom card of your library. You may cast it if it's a creature card. Otherwise, exile it.

Search your library for a creature or sorcery card, put it into your graveyard, then shuffle.
Reconstruct {2}{B} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)