msem-instigator

Draw a card.
Inscribe {1}{U} ({1}{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.)

Mill three cards, then you may return a creature or land card from your graveyard to your hand.

{2}{B}, Sacrifice Innocuous Sidekick and another creature: Create a 4/4 black Horror creature token with menace. Activate only as a sorcery.

When Inquisitive Pod enters, draw a card.
Whenever you cast your second spell each turn, Inquisitive Pod gets +3/+3 until end of turn.

Vigilance
When Inquisitive Student enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Whenever Insatiable Student attacks, you may sacrifice an artifact. When you do, tap target creature an opponent controls.

Enchant creature (Target a creature as you cast this. This card enters attached to that creature.)
Enchanted creature gets +2/+3 and has lifelink.

Whenever you cast your first instant or sorcery spell each turn, untap equipped creature.
Equip {1}

Inscrutable Realms enters tapped unless you control two or more other lands.
{T}: Add {W}.
{T}, Pay 1 life: Add {G} or {U}.

Whenever a creature you control dies, Insidious Terror gets +1/+0 and gains menace until end of turn.

Insightful Blow deals 3 damage to target attacking or blocking creature. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

{1}{W}, {T}: Tap target creature.
Put a -1/-1 counter on Insistent Ingenue: Untap Insistent Ingenue.

Draw a card.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)

Enchant creature
Enchanted creature gets +1/+2.
Whenever enchanted creature attacks, scry 1.

When Inspired Blade enters, if you control another Warrior, draw a card.

Creatures you control get +2/+1 until end of turn.

Harmony — Target creature gets +2/+2 until end of turn.
When Inspiring Band enters, harmonize. (Trigger up to one harmony of one permanent you control.)

{1}{W}, {T}: Other creatures you control get +1/+1 until end of turn.

Harvest (You may tap any number of creatures you control as you cast this spell. If you do, reduce this spell's mana cost by their total power.)
Draw three cards.

Creatures you control get +1/+1 until end of turn. Token creatures you control get an additional +1/+1 until end of turn.

Whenever Instability Elemental enters or you draw a card except during your draw step, target creature gets +1/+1 until end of turn.

Enchant creature
Enchanted creature gets +3/+0 and has haste and menace.

When Insurgent Racketeer enters or dies, you may discard a card. If you do, draw a card.

Equipped creature gets +1/+2.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Target creature gets +1/+1 until end of turn for each creature token you control.
Put the bottom card of your library into your hand.