msem-instigator

Destroy target land. Into the Maw of Hell deals 13 damage to target creature.

When Into the Unknown enters, create two 1/1 Scout creature tokens that are all colors.
Whenever a land you control enters, if it doesn't have the same name as another land you control, put a +1/+1 counter on each creature you control.

Put a +1/+1 counter on each creature you control. Until end of turn, creatures you control gain vigilance and “When this creature dies, create a 1/1 white Human creature token.”

Improve {W} ({W}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
Whenever one or more embattled creatures you control attack, create a 1/1 white Cleric creature token with lifelink. (A creature is embattled if it has a counter on it or has a permanent you control attached to it.)

Flash
When Intrepid Shooter enters, it deals 2 damage to target attacking creature.

Advance {4}{R} (Cast this for {4}{R} to advance it as it enters. {4}{R}: Advance this as a sorcery.)
Whenever Intruder Drone advances, exile the top card of your library. You may cast a spell exiled with Intruder Drone with mana value 3 or less without paying its mana cost.

Counter target spell unless its controller pays {1}.

Untap all creatures you control.
Draw a card.

At the beginning of your upkeep, rouse 1. Then if you control a creature with power 5 or greater, put a +1/+1 counter on each creature you control. (Put a +1/+1 counter on a permanent you control. If it isn't a creature, tap it and it becomes a 0/0 creature in addition to its other types.)

Equipped creature has hexproof.
{2}: Exile equipped creature. Return it to the battlefield under its owner's control at the beginning of the next end step.
Equip {1}

Draw a card for each Avatar you control.

Hexproof
Invisible Stalker can't be blocked.

Create two 2/2 blue Drake creature tokens with flying.
Metamorph {1}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

You may put a green creature card with mana value 4 or less from your hand onto the battlefield.
Ferocious — If you control a creature with power 4 or greater, that creature enters with two +1/+1 counters on it.

Search your library for a Demon card or a black card with mana value 6 or greater, reveal it, put that card in your hand, then shuffle.

When Ion Field enters, target player creates two 1/1 red Elemental creature tokens.
Whenever you cast an instant or sorcery spell that targets only one target, you may pay {1}{R}{R} and sacrifice Ion Field. If you do, copy that spell for each other target it could target. Each copy targets a different one of those targets.

If you've lost life this turn, you may cast this spell as though it had flash.
Irate Retribution deals X damage to each creature and each planeswalker. You gain X life.

Iron Warden enters with two -1/-1 counters on it.
When Iron Warden dies, you may put its -1/-1 counters on target creature.
{R}: Iron Warden gets +1/+0 until end of turn.

First strike
Whenever you cast an artifact or enchantment spell, put a +1/+1 counter on Ironclad Infantry.

When Ironeyes Desperado is exiled from your library, you may pay {R}. If you do, cast it without paying its mana cost.
Haste

Embellish {3}{R}{R} (If you cast this spell for {3}{R}{R}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)
Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Ironsmash Drill-Delver desecrates a permanent, it deals 3 damage to any target.

Flash
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Cadence (Whenever you cast a spell, if its mana value is greater than this creature's power, put a +1/+1 counter on this creature.)
Whenever Irreguleopard deals combat damage to a player, permutate. (You may remove a counter from a creature you control. If you do, put two +1/+1 counters on a different creature you control.)

When Irrigation Trawler enters, reveal the top card of your library. If that card was a land card, put that card into your hand. Otherwise, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Whenever a creature you control dies, each opponent loses 1 life and you gain 1 life.
{2}{W}{B}: Ishim's Meddling becomes a 4/4 Angel creature with flying and vigilance until end of turn.