msem-instigator

At the beginning of each opponent's end step, that player gets a poison counter unless damage was dealt this turn.

Flying
Whenever Immaculate Clouddasher attacks, up to three target creatures gain flying until end of turn.

Enchant creature
Enchanted creature gets +3/+3 and has flying.

Indestructible
Immortal Child can't block creatures with greater power.

Enchant creature
Enchanted creature gets +1/+1, has flying and lifelink, and is a legendary artifact in addition to its other types.

Exile target creature card from a graveyard. Create a token that's a copy of that creature, except it's a colorless artifact. (It's not a creature.)

Exile target creature or enchantment. You gain 3 life.

Enchant creature
When Imperative Blessing enters the battlefield, draw a card.
Enchanted creature gets +2/+2.

First strike, vigilance
Partner with Commander Hyctaleon (When this creature enters the battlefield, 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.

Exile target artifact or enchantment. Its controller creates a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Wu Xing (Add effects based on the number of colors of mana spent to cast this spell.)
1 | Create X 1/1 colorless Spirit creature tokens.
5 | Put a +1/+1 counter on each creature you control.

If a source an opponent controls would deal 2 or more damage to you, prevent 1 of that damage.
Civilized — Instead prevent all but 1 of that damage if you control an artifact, a creature, and an enchantment.

First strike
When Imperial Dragoon enters the battlefield, target creature gets +2/+0 until end of turn.

As long as Imperial Proclaimer is on the battlefield, it has all names of nonlegendary creature cards in addition to its name.

At the beginning of each upkeep you may pay {W}. If you do, tap target creature.

Enchant creature
Enchanted creature can block any number of creatures each combat.

When Impervious Fortifications enters the battlefield, you gain life equal to the number of creatures you control.
Creatures can't attack you or a planeswalker you control unless their controller pays {2} for each creature they control that's attacking you.

Defender

Flying
When Imposing Sphinx enters the battlefield, exile target nonland permanent an opponent controls until Imposing Sphinx leaves the battlefield.
At the beginning of your end step, if you gained life this turn, you may exile Imposing Sphinx, then return it to the battlefield under your control.

Enchant creature
Enchanted creature can't attack, block, or be sacrificed.

Flying
Vanguard — Whenever a creature you control attacks alone, it gains first strike until end of turn.

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.”

This spell costs {2} less to cast if there's a storied card in your graveyard. (Enchantments and legendary cards are storied.)
Search your library for a storied card, reveal it, put it into your hand, then shuffle.

Trial 4 (As you cast this spell, an opponent of your choice may pay 4 life. If they don't, they fail the trial.)
Search your library for an Angel card, reveal it, put it into your hand, then shuffle. If the trial was failed, non-Angel, non-God creatures can't attack or block until your next turn.

Target creature you control gets +2/+2 until end of turn.
Compose (Then if you cast this from your hand, exile it and create a Saga token with “r3—You may cast a copy of this card from exile without paying its mana cost.”)