msem-instigator

Enchant creature
When Hypnotic Halo enters, 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.”)
{2}{W}{W}, Sacrifice Hypnotic Halo: Exile enchanted creature.

Harness (You may tap a creature you control as you cast this spell. If you do, reduce this spell's mana cost by that creature's power.)
Search target opponent's library for a creature or planeswalker card and put it onto the battlefield under your control. That player shuffles.

Exile all creature cards from target player's graveyard. For each creature card exiled this way, search that player's library for any number of cards with the same name as that card and exile them. Then that player shuffles.

{T}: Add {C}.
{3}{U}: Until end of turn, I's Observatory becomes a 1/4 creature. It's still a land. It has menace if {B} was spent to activate this ability, has first strike if {R} was spent, and assigns combat damage equal to its toughness rather than its power if {G} was spent.

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.

{1}{W}: Artifact creatures you control get +1/+1 until end of turn. Activate only once each turn.

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.

Cast this spell only before attackers are declared.
Target creature you control gets +X/+0 until end of turn and gains haste until end of turn, where X is its power. At the beginning of the next end step, sacrifice that creature if it attacked this turn.

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

Ice Path enters tapped.
As Ice Path enters, choose a color.
You may spend {C} as though it were mana of the chosen color.
{T}: Add {C}.

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.)

Whenever Icepeak Phantasm becomes the target of a spell or ability, an opponent may pay {2}. If they do, sacrifice it.

When Ichi-no-Oni enters, each player loses 2 life.

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.)

{T}: Add one mana of any color. You can't spend this mana to cast spells with mana value 3 or greater.
Revive {2}{G} ({2}{G}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost. Activate this ability only any time you could cast a sorcery.)

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.)

Enchant opponent
Cards in enchanted player's graveyard lose all abilities and all names.
If enchanted player would mill one or more cards, they instead mill that many cards plus X, where X is the number of Curses attached to them.

(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.