msem-instigator

Archive 3 (As this enters, shuffle the top three cards of your main library into a new face up library. Sacrifice this after the archived library is empty.)
Whenever you cast a spell from your hand, you may cast a card from the archived library with a lesser mana value without paying its mana cost.

[+1]: Create a token that's a copy of another target permanent. Exile that token at the beginning of your next upkeep.
[–3]: If it's not an extra turn, you take an extra turn after this one, then skip your next turn that's not an extra turn.
[–6]: Until end of turn, planeswalkers become copies of I, Queen of Eons, except they aren't legendary. Destroy all nonland, non-I permanents.

This spell costs {1} less to cast and can't be countered if it targets a cursed opponent.
Target opponent mills eight cards. Exile up to two nonland cards milled this way. Until the end of your next turn, you may cast those cards and mana of any type can be spent to cast those spells.

Whenever IG-2 Disassembler enters or attacks, you may sacrifice an artifact. When you do, IG-2 Disassembler deals 2 damage to target player or planeswalker.

Icecap Tortoise enters with three ice counters on it.
Icecap Tortoise has defender as long as it has an ice counter on it.
{1}{U}: Remove an ice counter from Icecap Tortoise.

Flash
When Icecrowned Fox enters, you may return target spell or permanent to its owner's hand.
Each untapped creature you control has “Ward—Discard a card.” (Whenever it becomes the target of a spell or ability an opponent controls, counter it unless that player discards a card.)

You may have Icefang Wurm assign its combat damage as though it weren't blocked.
{4}{G}{G}: Monstrosity 3. (If this creature isn't monstrous, put three +1/+1 counters on it and it becomes monstrous.)

Target creature gets -2/-1 and gains winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)

Menace
When Icilica's Icestrider enters, choose one —
• Draw a card if you own a card in exile.
• Target player discards a card if that player owns a card in exile.

{1}, {T}: Tap target artifact, creature, or land.

Mill two cards, then you may return an instant or sorcery card from your graveyard to your hand.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

(Activate each submodule once as a sorcery. When this enters, activate one submodule for free.)
{R}{R}{R}: Bold
Any player may have Identity Module deal 5 damage to them. If no one does, draw three cards.
{R}{R}{R}: Brash
Identity Module deals 3 damage to any target.
{R}{R}{R}: Burning
Identity Module gains “Players can't gain life” and “At the beginning of each player's upkeep, Identity Module deals 2 damage to that player.”

When Ideologize enters, exile target creature an opponent controls and each other permanent with the same name that player controls. When Ideologize is no longer on the battlefield, return a card exiled with it to the battlefield under its owner's control.

Whenever you cast a spell, you may cast a spell from your hand with lesser mana value without paying its mana cost.
You can't cast more than one spell of each card type each turn.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When Idleglen Instructor enters, draw a card, then discard a card.

Each nontoken land you control has all activated abilities of each other land on the battlefield.
When Idyll leaves the battlefield, until the end of your next turn, you gain “Each nontoken land you control has all activated abilities of each other land on the battlefield.”

Flying, vigilance, lifelink
Idyllic Pegasus gets +1/+0 for each artifact and/or enchantment you control.

Search your library for an enchantment card, reveal it, put it into your hand, then shuffle.

When Iekin's Portal enters, look at the top five cards of your library. Put one into your hand and the rest into your graveyard.
{1}{U}{U}: Transform Iekin's Portal. Activate only if your fealty to Islands is five or greater.

Augmented — When you cast If Memory Serves, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, copy it twice. You may choose new targets for the copies.
Return target permanent card with mana value 3 or less from your graveyard to the battlefield. Exile If Memory Serves.

Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
Ifram's Greenfur must be blocked each combat if able.

{G}{U}{R}, Discard a card named Ifram, God of Chaos: Ifram gains indestructible and becomes a God creature in addition to its other types.
Whenever Ifram enters or attacks, choose target non-God permanent. Its owner shuffles it into their library, then its controller reveals the top card of their library. If it's a permanent card, they put it onto the battlefield.

Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Igneous Pulverizer desecrates a permanent, destroy target nonland permanent.

Ward—Pay 3 life.
Igniderm enters with three ignition counters on it.
At the beginning of your upkeep, remove an ignition counter from Igniderm. If you can't, sacrifice it.

At the beginning of combat on your turn, gain control of another target permanent until end of turn. Untap that permanent. It gains haste until end of turn.
Fleeting {2}{R}{R} (You may cast this spell for its fleeting cost. If you do, sacrifice it at the beginning of the next end step.)