msem-instigator

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

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.

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

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.

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

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.)

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.

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.

Indestructible
You have no maximum hand size.
Whenever an opponent draws a card, you draw a card.
If you would lose the game other than for having 0 or less life, you win the game instead. (Another player winning the game does not cause you to lose the game.)

Flying
When Illusionary Steed becomes the target of a spell or ability, sacrifice it.

Flash
Whenever you make first contact, you may put a card you own from outside the game into your hand. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Shuffle any number of cards from your graveyard into your library.
Scry 1, then draw a card.

Imitator of Drakes has flying as long as it has a +1/+1 counter on it.
{2}{U}: Put a +1/+1 counter on Imitator of Drakes.

You may have Imitator of Success enter as a copy of any creature on the battlefield, except it has no mana cost and base power and toughness 1/1 if it's a token.
Successor {1}{U}{U} ({1}{U}{U}, Exile this card from your graveyard: Create a token that's a copy of this card, except it has no mana cost and base power and toughness 1/1. Succeed only as a sorcery.)

Tap target creature. It doesn't untap during its controllers next untap step.
Judge target creature you control. (Honor it by putting a +1/+1 counter on it or condemn it by sacrificing it to draw a card.)

Draw three cards.
Lifecycle {3} ({3}, Discard this card: Create two tapped 1/1 colorless Elemental creature tokens.)

Draw a card.
Civilized — Instead draw two cards if you control an artifact, a creature, and an enchantment.

When Imperial Artisan enters, draw three cards, then put two cards from your hand on top of your library in any order.

When Imperial Diplomats enters, if it's not a token, create a token that's a copy of it, except it has no mana cost.
{T}, Tap an untapped creature you control: Draw a card, then discard a card.

Mill four cards, then return a noncreature card from your graveyard to your hand.

Draw a card. Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Enchant land you don't control
Whenever enchanted land becomes tapped, you may draw a card.

{U}, Sacrifice Imperious Nixie: Return target creature to its owner's hand.

Lionize {1}{U} ({1}{U}, Exile this card from your hand: Put a +1/+1 counter on target creature and it gains the following ability until end of turn. You may cast this card on a later turn from exile.)
Hexproof