msem-instigator

Whenever a land you control enters, you may have target creature get +1/+0 and gain first strike until end of turn.

Whenever Infiltrator of the Anomalous deals combat damage to a player, add {R}. Until end of turn, you don't lose this mana as steps and phases end.

Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.
{8}{G}, Exile Influence of Kruphix from your graveyard: Return up to two target cards from your graveyard to your hand.

When Influential Wildborn enters, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)
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.)

Target creature you control has base power and toughness 5/5 and gains trample until end of turn.

{3}, {T}: Put Ing'Wei's Crystal Top on top of your library. Scry 3, then draw a card.

Whenever you cast a spell, untap Inglorious Blaze.
{T}: Inglorious Blaze deals 1 damage to target player or planeswalker.

When Ingredient Scroungers enters, if you control a creature with deathtouch, return target permanent card from your graveyard to your hand.

Injustice deals 4 damage to target creature. Post a bounty on up to one other target creature. (Put a bounty counter on that creature. It has “When this creature dies, each opponent draws a card” as long as it has a bounty counter on it.)

Enchant creature
Enchanted creature gets +2/+0 and has trample.

Whenever a creature you control enters for the second time each turn, it gains haste until end of turn. You may have it get +1/+1 until end of turn.

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

Inquirer, Roaming Rover attacks each combat if able.
Whenever Inquirer deals damage to an opponent, draw a card.

Graft 1 (This creature enters with a +1/+1 counter on it. Whenever another creature enters, you may move a +1/+1 counter from this creature onto it.)
{T}: Add {C}.

Inquisitor's Chamber enters tapped.
{T}: Add {B}.
{B}{B}, {T}, Sacrifice another permanent: Draw a card.

Whenever Insatiable Abomination or another Horror you control enters, each player mills four cards.
Exile a creature card from your graveyard: Tap target Horror you control. It gains indestructible until end of turn.

Whenever you cast your first instant or sorcery spell each turn, untap equipped creature.
Equip {1}

{4}, {T}: Put a -1/-1 counter on target creature.
{4}, {T}: Remove a -1/-1 counter from target creature.

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

At the beginning of your upkeep, put a lore counter on Inspirational Copse, discard your hand, then draw a card for each lore counter on Inspirational Copse.

Trial 3 (As you cast this spell, an opponent of your choice may pay 3 life. If they don't, they fail the trial.)
When Inspired Trialmaker enters, if the trial was failed, add {R}{W}{B}.

{2}, {T}: Put a +1/+1 counter on target creature you control.
{2}, {T}, Sacrifice Inspiring Effigy: Put a +1/+1 counter on each creature you control.

Scry 3, then reveal the top card of your library. Discard your hand, then draw cards equal to that card's mana value.

Whenever Inspiring Tactician or another permanent you control becomes the target of a spell or ability you don't control, amass Soldiers 1. (Put a +1/+1 counter on an Army you control. It's also a Soldier. If you don't control one, create an 0/0 black Soldier Army creature token first.)

Whenever you cast or copy an instant or sorcery spell this turn, Instant of Brilliance deals 1 damage to each opponent.
Copy target instant or sorcery spell you control. You may choose new targets for the copy.