msem-instigator

Discard your hand, then draw two cards.
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.)

[+1]: Whenever a creature you control attacks this turn, Aleryn, Dungeon Disabler deals 1 damage to the defending player.
[–1]: Add X mana in any combination of {R} and/or {G}, where X is the number of creatures you control.
[–6]: You get an emblem with “Whenever a player casts a spell, this emblem deals 3 damage to any target.”

Pressure {3}{B} (You may cast this spell for its pressure cost if seven or more cards are in your graveyard.)
When Oryxyth's Brood enters, you draw two cards and you lose 2 life.

Defender

Other creatures you control can't attack or block alone.

Vanishing 5 (This creature enters with five time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.)
{1}{R}, Remove a time counter from Unstable Magmaling: Flip a coin. If you win the flip, it deals 3 damage to any target.

As Tree of Timelines enters, you may pay 3 life. If you don't, it enters tapped.
{T}: Add {B}, {G}, or {U}.

{T}: Add {C}.
Civilized — {T}: Add {C}{C}. Activate only if you control an artifact, a creature, and an enchantment.

When Graygulch Lurker dies, target opponent loses 2 life.

{1}, Sacrifice a creature: Each opponent loses 1 life.
Whenever a creature dies, you gain 2 life.

When Serum Peddler enters, you draw a card and you lose 1 life.

When Wilderness Forager enters, you may reappropriate. If you do, gain 6 life. Otherwise, gain 3 life. (To reappropriate, exile exactly two cards from your hand and/or graveyard.)

Embellish {3}{R}{R} (If you cast this spell for {3}{R}{R}, create a 1/1 blue Thopter artifact creature token with flying when it enters.)
Desecrate (When this creature enters, you may sacrifice an artifact or land.)
When Ironsmash Drill-Delver desecrates a permanent, it deals 3 damage to any target.

When this artifact enters, draw a card.
{1}, {T}, Sacrifice this artifact: Target creature seeks valor. Activate only as a sorcery. (Give it that Oath Aura. Fulfill it by it dealing combat damage to a player to create a 2/1 white Soldier token.)

Flying
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
Whenever Zaidha, Seraph of Calamity deals combat damage to a player, choose up to two target nonland permanents that player controls and target nonland permanent you control. Destroy one of those permanents at random.

Choose one —
• Fuel for the Fire deals 5 damage to target creature or planeswalker. Its controller creates a tapped Treasure token. If a permanent dealt damage this way would die this turn, exile it instead.
• Exile target artifact. Its controller creates a tapped Treasure token.

Foretell {2}{U} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)
Put target nonland permanent on top of its owner's library.
Scry 2.

Mechanized Ideal gets +X/+Y, where X is the highest base power among other creatures you control and Y is the highest base toughness among other creatures you control.

{2}{G}: Exile up to three cards from graveyards. Autocrat X, where X is the number of cards exiled this way. (If you don't control an autocrat, put X +1/+1 counters on this. It becomes an autocrat until it has no +1/+1 counters on it.)
Whenever Hegemony Monarch attacks, you may exile target card from a graveyard. If you do, untap it and it gains trample until end of turn.

Draw a card.
Leitmotif (If you cast this spell from your hand, exile it as it resolves. When you next cast a spell that shares a color with this card, you may cast this from exile without paying its mana cost.)

At the beginning of your end step, draw a card.
Whenever a creature deals combat damage to you, that creature's controller gains control of Ambition's Crown.

First strike
As long as it's your turn, other creatures you control get +1/+0.

Return target artifact, enchantment, or planeswalker card with mana value 3 or less from your graveyard to the battlefield.

Hazy Summits enters tapped.
{T}: Add {R} or {W}.
{1}, {T}: Add one mana of any color.

When Chantwood Channeler enters from your graveyard, it gains haste and creatures you control get +3/+3 and gain trample until end of turn.
{5}{G}{G}{G}, Sacrifice a creature: Return Chantwood Channeler from your graveyard to the battlefield. Activate only as a sorcery.