msem-instigator

Create two 1/1 green Elf creature tokens, then up to one target creature gets +X/+X until end of turn, where X is the number of creatures you control. (Targets are chosen before the tokens are created.)

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.)

Put a +1/+1 counter on target creature. It gains indestructible until end of turn.

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

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.

Gain control of target creature until end of turn. Put a +1/+1 counter on it and another target creature you control and untap them. Those creatures gains haste until end of turn.

Target opponent reveals cards from the top of their library until they reveal two instant and/or sorcery cards. Exile those cards, then that player shuffles the rest into their library. You may cast cards exiled this way until end of turn, and you may cast them without paying their mana costs.

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.)

Look at the top eight cards of your library. You may put a creature card from among them onto the battlefield and exile an instant or sorcery card from among them. Put the rest on the bottom of your library in a random order. As long as that creature is on the battlefield, whenever it deals combat damage to a player, copy the exiled card and you may cast the copy without paying its mana cost.

Destroy target artifact or enchantment. You gain 4 life.

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.

Enchant creature
Enchanted creature can't attack or block, can't be sacrificed, and its activated abilities can't be activated.

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.

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.

Choose one —
• Ire of Ancient Tomes deals 2 damage to any target.
• Target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost.

Flying (This creature can't be blocked except by creatures with flying or reach.)
When Iridescent Familiar enters, if you control another creature with flying, draw a card.

Flash
Deathtouch, lifelink
Whenever Irika, Wielder of Secrets deals combat damage to a player, you may pay {U/B}. If you do, you draw a card and you lose 1 life.

{T}: Add {G}.
{T}: Add one mana of any color. Activate only if you control another Dryad.

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.