msem-instigator

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)
Enchanted creature can't attack or block.
At the beginning of your upkeep, you gain 1 life.

Advance {3}{W}{W} (Cast this for {3}{W}{W} to advance it as it enters. {3}{W}{W}: Advance this as a sorcery.)
Whenever Inconspicuous Loxodon advances, search your library for an Equipment card, put it onto the battlefield, then shuffle.
As long as Inconspicuous Loxodon is enchanted or equipped, he's a 5/5 legendary Elephant Rogue named Agent E.

Sacrifice Indomitable Bear: Creatures you control gain indestructible until end of turn.

Flash
Enchant creature
When Ineffable Patronage enters the battlefield, it deals 4 damage to up to one target attacking or blocking creature.
Enchanted creature gets +2/+2.

Whenever a creature enters the battlefield under your control, you may have target creature get +1/+1 and gain flying until end of turn.

Enchant creature
When Inherited Blessing enters, remove all -1/-1 counters from each creature you control.
Enchanted creature gets +2/+2 and has first strike.

Create a 3/3 white Construct enchantment creature token.

Put two +1/+1 counters on target creature. (Cast a copy of this spell once while this creature is on the battlefield.)

Put a +1/+1 counter on target creature.
Inscribe {2}{W} ({2}{W}: 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.)

Target creature gains lifelink until end of turn. Untap that creature.
Inscribe {1}{W} ({1}{W}: 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.)

Target creature gets +1/+3 until end of turn. (Then exile this card. You may cast the creature later from exile.)

Creatures can't attack you or planeswalkers you control unless their controller pays {X} for each of those creatures, where X is the number of attacking creatures.

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

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.

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

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

Harmony — Target creature gets +2/+2 until end of turn.
When Inspiring Band enters the battlefield, 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.

Enchant creature
Whenever enchanted creature attacks, other creatures you control get +1/+2 until end of turn.

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

Inspirited Duelist has double strike as long as it has a +1/+1 counter on it.

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.

Whenever a +1/+1 counter is put on a creature you control, scry 1.
Each creature you control with a +1/+1 counter on it has lifelink.

Flying
{1}{W}: Exile target artifact you control. Return that card to the battlefield under your control at the beginning of the next end step.