msem-instigator

Choose target spell. Scry 3, then reveal the top card of your library. Counter the chosen spell unless its controller pays {X}, where X is that card's mana value. (To scry 3, look at the top three cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Counter target noncreature spell unless its controller pays {2}.

Flash (You may cast this spell any time you could cast an instant.)
When Spell Shackle enters, exile target instant or sorcery spell. (That spell won't resolve.)
{1}{U}, Sacrifice Spell Shackle: Cast the exiled card without paying its mana cost.

As an additional cost to cast this spell, put a -1/-1 counter on a creature you control.
Counter target spell.

You may cast this spell without paying its mana cost if it's the only card in your hand.
Counter target spell.

Enchant creature
When Sphinx's Advice enters, draw a card.
Enchanted creature has flying.

Once each turn, when one or more cards are put into an opponent's graveyard from their library, you may draw a card.

Prevent all combat damage that would be dealt to and dealt by target creature this turn.
Inscribe {2}{U} ({2}{U}: 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.)

Counter target creature spell.
Permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

This spell costs {2} less to cast if you control a creature with flying.
Tap up to two target creatures. Put a stun counter on each of them. (If a permanent with a stun counter would become untapped, remove one from it instead.)

Choose one —
• Target creature gets +1/+1 and gains hexproof until end of turn.
• Target creature gets -4/-0 until end of turn.
• Scry 1, then draw a card.

Exile target artifact, creature, or enchantment. Return that card to the battlefield under its owner's control at the beginning of the next end step.
Draw a card.

Whenever a nontoken creature you control perseveres, create a 1/1 blue Nymph creature token with flying. (A creature perseveres when it survives damage.)

Cast this spell only if an opponent controls a creature with power 5 or greater or you control six or more lands.
Return all nonland permanents target player controls to their owner's hand.

Draw a card. Scry 2.
Orchestrate {U} (You may exile this card from your hand anytime you could cast a sorcery for its orchestrate cost. When you next resolve a spell, you may cast this from exile without paying its mana cost.)

Counter target artifact or sorcery spell.

Enchant creature or enchantment
Enchanted permanent doesn't untap during its controller's untap step.
Enchanted permanent can't have counters put on it.

Until end of turn, creatures and artifacts you control gain “{T}: Tap target permanent.”

Whenever you draw a card, put a dream counter on Stargazing.
Remove seven dream counters from Stargazing and exile it: Shuffle your hand and graveyard into your library, then draw seven cards.

Draw two cards. If you have no cards in hand and there are no cards in your graveyard, draw seven cards instead.

This spell costs {2} less to cast if you cast it during your main phase.
Tap up to two target creatures. Put a stun counter on each of those creatures.

(Transform this if it's not attached to a creature. Pay {2}{U} as a sorcery to unattach it.)
Enchant creature you control
Steed of the Loch's rider gets +2/+1.
Whenever Steed of the Loch's rider attacks, you may tap target creature an opponent controls.

Enchant creature
When Sticky Fingers enters, draw a card.
Enchanted creature gets +2/+0 and can't be blocked.

Counter target noncreature spell. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Take an extra turn after this one. At the beginning of that turn's upkeep, if you control a legendary creature, each opponent exiles the top card of their library. Until the end of that turn, you may play those cards and you may spend mana as though it were mana of any type to cast those spells.
Exile Stolen Moments.