msem-instigator

Flying
Whenever Herald of Shadow attacks, another target creature can't be blocked this turn.
Whenever a creature you control deals combat damage to an opponent, exile the top card of that player's library. You may play that card for as long as it remains exiled, and you may spend mana as though it were mana of any color to cast it.

Flying, prowess
If you would draw a card, scry 1, then draw a card instead.
Whenever an opponent casts a spell, if it's not their turn, draw a card.

Whenever Hero of Aer attacks, it gets +2/+1 until end of turn.

Equipped creature gets +3/+1 and has haste.
Equip Soldier or Warrior {1}
Equip {4}

Choose two —
• Create two 1/1 white Soldier creature tokens.
• Creatures you control get +1/+1 until end of turn.
• You gain 5 life.
• Choose a creature. It gains indestructible until end of turn.

Whenever Hero's Henchman attacks, another target creature you control gets +1/+1 until end of turn.

Return target creature card with mana value 3 or less from your graveyard to the battlefield.
Draw a card.

Create two 1/1 white Soldier creature tokens. You gain 4 life.

Reach
When Hoarding Arachnid dies, draw a card.

Equipped creature has respawn. (When this creature dies, if it attacked this turn, return it to its owner's hand.)
Equip {1}

Flying
Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Honorable Mentor mentors a creature, that creature and Honorable Mentor each gain first strike until end of turn.

Flying, vigilance
At the beginning of your end step, if a creature you control dealt combat damage to an opponent this turn, put a +1/+1 counter on Horizon Prophet.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you attack, add a quest counter.
Upgrade target creature you control. (Give it one of the listed counters it doesn't already have.)
• +1/+1
• Deathtouch
Target attacking creature fights up to one other target creature.
​

Enchant creature
Enchanted creature has “{T}: This creature deals 1 damage to any target. If this is the second time this ability has resolved this turn, it deals 5 damage to that target instead.”

Glitch {2} (Remove one [restriction] for each time you pay the glitch cost.)
Return target creature [you control] to its owner's hand.
Draw a card.

As long as it's your turn, equipped creature has first strike and deathtouch.
If equipped creature would deal damage to a player or planeswalker, it deals four times that damage to that player or planeswalker instead.
Equip {4}

{T}, Sacrifice Ilhus, Knight of Zarad: Destroy all creatures.

Flying
Illuminated Firebird can't block.
Foresight — Whenever you draw your second card each turn, return Illuminated Firebird from your graveyard to the battlefield.

Indestructible
Immortal Child can't block creatures with greater power.

Flying
When Imposing Sphinx enters, exile target nonland permanent an opponent controls until Imposing Sphinx leaves the battlefield.
At the beginning of your end step, if you gained life this turn, you may exile Imposing Sphinx, then return it to the battlefield under your control.

Glitch {2} (Remove one [restriction] for each time you pay the glitch cost.)
Improbable Aim deals damage to target creature or planeswalker equal to the number of [instant and sorcery] cards in your graveyard.

This spell can't be countered.
Inescapable Blaze deals 6 damage to any target.

When Ingredient Scroungers enters, if you control a creature with deathtouch, return target permanent 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.

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