msem-instigator

{T}, Sacrifice a land: Destroy target land.

Escalate {R} (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Untap all creatures you control.
• Take an extra turn after this one. Skip the untap step of that turn. Exile Inspire Actuality.

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

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

At the beginning of your upkeep, reveal the top card of your library. Any opponent may have Insurgent Ballads deal damage to them equal to that card's mana value. If a player does, put that card on the bottom of your library. Otherwise, put it into your hand.

Exile the top card of your library. Until end of turn, you may play that card. If that card is an instant or sorcery card, it costs {2} less to cast this turn.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
{U}{R}: Target creature without prowess gains prowess until end of turn. Activate only if Intelligence is in your graveyard.

Flying, ward {1}
Intisuyu's Masterpiece gets +X/+X, where X is the number of artifacts and/or enchantments you control.

(As this Saga enters and after your draw step, add a lore counter. Sacrifice after III.)
I, II — Put a +1/+1 counter on target creature you control.
III — Double the number of counters on target creature you control.
​

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.

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

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.)

Look at the top X cards of your library, where X is two plus the number of creatures you control. Exile up to two of them, then put the rest on the bottom in a random order. You may play the exiled cards until the end of your next turn.

Codex — Little Pig; Charging Cassowary; The Lonely Hunter; Shadowlurk; Blood Constrictor. (As this enters, conjure its contents into a shuffled face-up additional library.)
You may cast Adventures of this codex's contents from your graveyard.

[+1]: Create a tapped 3/3 black Crocodile creature token with menace.
[–1]: You may cast a copy of Size Up.
[–7]: Each land you control becomes a 3/3 Crocodile creature and gains menace and haste until end of turn.

Flying, lifelink
Whenever another creature you control attacks, until end of turn, that creature gets +2/+0 if it's red, +0/+2 if it's green, gains lifelink if it's white, and gains flying it if it's blue.

Flying, trample, lifelink

Indestructible
As long as your devotion to red and white is less than seven, Iroas isn't a creature.
Other creatures you control have first strike.
Whenever you attack for the first time each turn, untap all other creatures you control. After this phase, there is an additional combat phase.

Protection from mana values lower than Ironwood Elemental's power (This permanent can't be blocked, targeted, dealt damage, or enchanted by anything with mana value lower than this creature's power.)
Ironwood Elemental's power and toughness are each equal to the number of creatures you control.

When Irreverent Sinscape enters, destroy up to one other target nonland permanent.
When Irreverent Sinscape dies, exile it. When you do, you may exile any number of cards from your graveyard that have four or more card types among them. If you do, return a permanent card from a graveyard to the battlefield under your control. You may repeat this process any number of times.

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.

Menace
Whenever Issbarren Creeper deals combat damage to a player, draw a card, then discard a card.