msem-instigator

Once each turn, when a player casts a spell, you may choose two target players. Each of those players exiles cards from the top of their library until they exile a nonland card with mana value less than that spell's. They may cast those cards without paying their mana cost. Then they put the rest of the exiled cards on the bottom of their library in a random order. (The active player puts their spell on the stack first.)

Indestructible
At the beginning of each player's upkeep, target permanent you control gains protection from everything until end of turn. Then if you control at least five permanents whose colors are exactly different color triads, you win the game.

Exile all cards from your graveyard. You may search your library for any number of instant and/or sorcery cards with different names that share a name with one or more cards exiled this way and cast them without paying their mana costs, then shuffle. Exile Infuse the Apparatus.

Hexproof
Whenever another creature you control becomes the target of a spell an opponent controls, you may submerge that creature. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)
{1}{U}{U}: Turn target face-down creature you control face up.

{3}, {T}: Put Ing'Wei's Crystal Top on top of your library. Scry 3, then draw a card.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
[+1]: Scry 1. If you're in a renaissance, draw a card.
[–2]: Return target nonland permanent to its owner's hand if its mana value is 3 or less or if you're in a renaissance.
[–6]: Create two 8/8 blue Kraken creature tokens. If you're in a renaissance, take an extra turn after this one.

[+1]: Look at the top two cards of your library. Put one of them into your hand and the other into your graveyard.
[–2]: Return target card from your graveyard to the battlefield face down.
[–6]: Turn any number of face-up nonland permanents of your choice face down.

Flying, prowess
Whenever you cast a noncreature spell, untap Ingenious Trickster.

Whenever Inishtu, Desert Healer enters or attacks, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
At the beginning of your upkeep, if seven or more cards are in your graveyard, you may transform Inishtu.

Indestructible
{2}{B}, Exile two cards from your graveyard: Each opponent loses 2 life and you gain 2 life.

At the beginning of your end step, if you lost 2 or more life this turn, create a 1/1 black Bird creature token with flying. If you lost 4 or more life this turn, instead create a 3/3 black Cat creature token with deathtouch. If you lost 6 or more life this turn, instead create a 5/5 black Golem creature token with trample.

Whenever Inkwell Daggers enters or attacks, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

Whenever a creature you control enters for the second time each turn, it gains haste until end of turn. You may have it get +1/+1 until end of turn.

{T}, Sacrifice a land: Destroy target land.

Inquirer, Roaming Rover attacks each combat if able.
Whenever Inquirer deals damage to an opponent, draw a card.

Whenever Inquisitive Guardian deals combat damage to an opponent, you may exile a nonland card from your graveyard. If you do, draw a card.
{U}: Inquisitive Guardian gains flying until end of turn.

[+1]: Each opponent puts a -1/-1 counter on a creature they control.
[–1]: Exile target card in a graveyard. You gain life equal to its mana value.
[–6]: Choose a number. You draw that many cards and you lose that much life.

{3}{B}, {T}: Choose a card name. Target player reveals cards from the top of their library until they reveal a card with the chosen name. If they do, put the revealed cards into their graveyard. Otherwise, they shuffle their library.

Inquisitor's Chamber enters tapped.
{T}: Add {B}.
{B}{B}, {T}, Sacrifice another permanent: Draw a card.

Whenever Insatiable Abomination or another Horror you control enters, each player mills four cards.
Exile a creature card from your graveyard: Tap target Horror you control. It gains indestructible until end of turn.

You may have Insipid Metamorph enter as a copy of any other creature on the battlefield, except it's 1/1.

At the beginning of your upkeep, put a lore counter on Inspirational Copse, discard your hand, then draw a card for each lore counter on Inspirational Copse.

Escalate {R} (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Untap all creatures you control.
• Take an extra turn after this one. Skip the untap step of that turn. Exile Inspire Actuality.

{2}, {T}: Put a +1/+1 counter on target creature you control.
{2}, {T}, Sacrifice Inspiring Effigy: Put a +1/+1 counter on each creature you control.

Whenever you cast or copy an instant or sorcery spell this turn, Instant of Brilliance deals 1 damage to each opponent.
Copy target instant or sorcery spell you control. You may choose new targets for the copy.