msem-instigator

Immolated Grave enters tapped.
{T}: Add {R}.
{2/R}{2/R}: Immolated Grave becomes a 3/1 red Elemental creature with first strike until end of turn. It's still a land.

When Imperfect Stone enters, mill three cards.
{T}: Add one mana of any color.

As Imperial Barracks enters, you may reveal a Mountain or Plains card from your hand. If you don't, Imperial Barracks enters tapped.
{T}: Add {R} or {W}.

{T}: Add {C}.
{4}, {T}, Put a -1/-1 counter on a creature you control: Draw a card.

Spirited (When this enters, you may activate one of its activated abilities without paying its cost.)
{1}, {T}: Add one mana of any color. When you do, surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Equipped creature gets +3/+2.
Equip {3}

Imperial Marketplace enters with a charge counter on it.
{T}: Add {C}.
{T}, Remove a charge counter from Imperial Marketplace: Put a +1/+1 counter on target creature you control.

{T}: Add {C}. Activate only if you have less life and control fewer creatures than each opponent.

{T}: Add {C}.
{1}, Discard Imperial Port: Search your library for a basic land card, reveal it, and put it into your hand. Then shuffle.

Spirited (When this enters, you may activate one of its activated abilities without paying its cost.)
{2}, Sacrifice Imperial Silks: Draw a card.
{2}, Sacrifice Imperial Silks: You gain 3 life.

Flash
You may cast this spell from your graveyard, but not from anywhere else. When you do, destroy target permanent.

{T}: Add {C}.
{T}: Add {C}{C}{C}. Spend this mana only to pay advance costs.

Harmony — Target creature gains indestructible until end of turn.
When Improvising Automaton enters, harmonize. (Trigger up to one harmony of one permanent you control.)

Equipped creature gets +3/+2 and must be blocked by a creature that doesn't share a color with it if able.
Equip {4}

{T}: Add {C}.
{5}, {T}: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

{T}, Pay 1 life: Add {B} or {R}.
{2}, {T}, Sacrifice Industrial District and another permanent: Draw a card. Activate only during your turn.

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

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

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

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}.

{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.

Equipped creature gets +1/+2.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

({T}: Add {U}.)
Interlocked Waterways enters tapped.
{U}, {T}, Reveal a blue card from your hand: Untap target creature.