msem-instigator

{T}: Add {C}.
{1}, {T}, Sacrifice House of Forgotten Whispers: Draw a card.

When Ikari-no-Oni enters, other creatures you control get +1/+0 until end of turn.

Whenever Imako, Ninefingers becomes tapped, exile the top three cards of target opponent's library face down.
You may look at cards exiled with Imako.
Sacrifice Imako: Turn all cards exiled with it face up. Exile all cards with those names from your opponent's graveyards.

First strike, vigilance
Partner with Commander Hyctaleon (When this creature enters, target player may put Commander Hyctaleon into their hand from their library, then shuffle.)
At the beginning of your upkeep, you may search your library for a Soldier card, reveal it, put it into your hand, then shuffle.

When Imperial Artisan enters, draw three cards, then put two cards from your hand on top of your library in any order.

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

Look at target player's hand. You may choose a nonland card from it. If you do, that player reveals that card, puts it on the bottom of their library, then draws a card.

Enchant creature
Enchanted creature has “Whenever this creature attacks, if there are at least two other attacking creatures, this creature gains +2/+2 until end of turn.”

Enchant creature
Enchanted creature has “{R}, {T}: Create an X/1 red Elemental creature token with haste and trample, where X is this creature's power. Exile that token at the beginning of the next end step.”

Haste
When Inferno Forerunner enters, you may have target creature gain haste until end of turn.

Target creature gains lifelink until end of turn. Untap that creature.
Inscribe {1}{W} ({1}{W}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

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

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

Insightful Blow deals 3 damage to target attacking or blocking creature. Investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

When Ironsmash Wrecker enters, you may destroy target artifact.

Haste (This creature can attack and {T} as soon as it comes under your control.)

First strike (This creature deals combat damage before creatures without first strike.)
Whenever a creature you control becomes blocked by a creature, Itava Scourge deals 1 damage to that creature's controller.

Menace (This creature can't be blocked except by two or more creatures.)
Itava Warshrieker attacks each combat if able.

Art of war — At the beginning of your end step, if Jaakuna Betrayer dealt damage to an opponent this turn, you may discard a card. If you do, draw a card.

When Jaakuna Bloodsworn enters, any opponent may have it deal 3 damage to them. If a player does, sacrifice Jaakuna Bloodsworn.

Equipped creature gets +2/+0 and has “{T}, Unattach Javelin: It deals 2 damage to target creature.”
Equip {2}

When Jidai Clairvoyant enters, create a 2/2 colorless Spirit creature token.
Whenever a colorless creature you control enters, you may draw a card.

At the beginning of each player's upkeep, that player may sacrifice a creature. If they don't, they discard a card.

Creature spells you cast with power 4 or greater cost {1} less to cast.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
When Kalime Charger enters, you may have another target creature you control gain trample until end of turn.