msem-instigator

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.

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.)

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.

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.

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

Target creature you control deals damage equal to its power to another target creature.
Agonize (You may cast this card from your graveyard by putting a -1/-1 counter on a creature you control in addition to paying its other costs. Then exile this card.)

Target creature you control gets +2/+2 until end of turn. If it's blocked or blocking, it gets an additional +2/+2 until end of turn.

{T}: Add {C}.
{1}, {T}: Add one mana of any color.

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

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Spells you cast during combat cost {1} less to cast.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

Trample
When Ironhide Hadhayosh dies, put two +1/+1 counters on target creature you control.