msem-instigator

Whenever you cast an instant or sorcery spell from your hand, put that card onto the battlefield face down as a 2/2 creature instead of putting it into your graveyard as it resolves.
Whenever a face-down creature you control deals combat damage to an opponent, you may exile it. If you do, you may cast it without paying its mana cost.

First strike
{1}{R}: Hatsuo, Honored General and other Warrior creatures you control get +1/+0 until end of turn.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever another noncreature source deals damage to a creature or player, you may have Hav'za, Itavan Warchief deal half that damage, rounded up, to any target.

Untap all other Elves you control during each other player's untap step.
You may cast spells as though they had flash.

Ward—Sacrifice a permanent.
Whenever a player sacrifices a permanent, put a +1/+1 counter on Hayat, Hungering Bakhtak.
Surpass {4}{B}{G} ({4}{B}{G}: Transform this creature. This costs {1} less to activate for each counter on it. Activate only as a sorcery.)

Whenever you cast an instant or sorcery spell, look at the bottom card of your library. You may manifest it. If you don't, put it into your hand. (To manifest a card, put it onto the battlefield face down as a 2/2 creature. Turn it face up any time for its mana cost if it's a creature card.)

At the beginning of each player's upkeep, sacrifice Hayuan, the Misjudged if that player controls a creature with power 2 or less.
When Hayuan dies, create X Idol tokens, where X is the number of creatures you control. (They're artifacts with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Menace
At the beginning of your end step, He of All Hallow's Eve deals damage equal to its power to you unless you're horrific. (You're horrific as long as you've sacrificed a permanent or discarded a card this turn.)

[+1]: Tap target nonland permanent. It doesn't untap during its controller's next untap step.
[–2]: Exile target tapped nonland permanent.
[–4]: Target player skips their next untap step. Tap up to three target permanents.

[+1]: Create a 1/1 red Cleric creature token. If you control three or more Clerics, you may instead create Aspect of Faradia, a legendary 5/5 white Angel creature token with flying and vigilance.
[–1]: Exile target creature if you control an Angel. Otherwise, that creature can't attack or block and its activated abilities can't be activated until your next turn.
[–7]: Creatures you control get +5/+5 and gain flying and vigilance until end of turn.

[+2]: Until end of turn, Helene Trant becomes a 4/4 Human Warrior creature with hexproof and trample that's still a planeswalker. Prevent all damage that would be dealt to her this turn.
[–2]: Draw two cards.
[–4]: You get an emblem with “Whenever one or more creatures you control deal combat damage to a player, draw a card.”

During your turn, Helene is a 4/4 Human Warrior creature with hexproof and trample that's still a planeswalker. Prevent all damage that would be dealt to her during your turn.
[+1]: Create a green Stance enchantment token with “When a creature you control deals combat damage to an opponent, sacrifice this. If you do, draw a card.”
[–2]: Create a blue Stance enchantment token with “When an opponent casts a noncreature spell, sacrifice this. If you do, counter that spell.”

Infiltrate (Whenever one or more attacking creatures you control aren't blocked, this creature gets +1/+1 until end of turn.)
Other creatures you control have infiltrate.

[+1]: Up to two target creatures you control each get +1/+1 and gain vigilance until end of turn.
[–3]: Create two 1/1 white Dwarf Peasant creature tokens. You gain 2 life.
[–7]: You get an emblem with “Creatures you control get +2/+2 and have double strike.”

Indestructible
As long as your devotion to white is less than five, Heliod isn't a creature.
If an effect would create one or more kinds of tokens under your control, it creates an additional token of each kind.
{3}{W}: Put a +1/+1 counter on each other creature you control. Activate only as a sorcery.

[+2]: Until end of turn, up to one target creature you control gets +3/+3 and gains trample and vigilance.
[–2]: Destroy target artifact, enchantment, or tapped creature.
[–3]: Create a 1/1 green Insect creature token, a 2/2 white Cat creature token, and a 3/3 red Ox creature token.
[–8]: Until end of turn, creatures you control get +X/+X and gain trample and vigilance, where X is the number of creatures you control.

[–1]: Tap target nonland permanent. It doesn't untap during its controller's next untap step.
[–2]: Put target nonland permanent into its owner's library second from the top.
[–X]: Shuffle up to X cards from your hand into your library, then draw that many cards. You gain that much life.

Whenever a Project you control enters, create two 1/1 colorless Construct artifact creature tokens.
Whenever a creature leaves the battlefield, you may put a progress counter on a Project you control.

Whenever you cast a legendary spell or play a legendary land, put a +1/+1 counter on Henros, Royal Herald and you gain 1 life.
{2}{W}: Look at the top six cards of your library. You may exile a legendary card from among them. Then shuffle. If the exiled card has mana value less than Henros's power, you may put it onto the battlefield tapped. If you don't, put it into your hand.

This spell can't be countered.
Vigilance
Noncreature spells cost {1} more to cast.

[+1]: Each player may draw a card. For each opponent who does, you gain 4 life.
[–3]: Exile target nonland permanent. As long as that card remains exiled, its owner may pay {2} any time they could cast a sorcery. If they do, they return that card to their hand.
[–8]: Target opponent gets an emblem with “Creatures you control lose all abilities and have base power and toughness 1/1.”

[+1]: Until your next turn, if a source would deal damage to Heping, Master Arbitrator, prevent all but 1 of that damage.
[–2]: Create a white Aura enchantment token named Pacifism attached to target creature an opponent controls. It has enchant creature and “Enchanted creature can't attack or block.”
[–8]: You get an emblem with “At the beginning of your end step, your life total becomes 20.”

Flying, haste
Whenever you attack with three or more creatures, harmonize three times. (To harmonize, trigger up to one harmony of a permanent you control.)
If you would harmonize, you may instead return Herald of Festivities from your graveyard to your hand.

First strike, lifelink
Once each turn, when another nontoken creature you control dies, you may create a 2/2 white Elk Spirit creature token with first strike and lifelink named Fawn of Hesediel.

[+1]: Add {G}{U}{R}. Spend this mana only to cast creature spells.
[–2]: Reveal the top card of your library. If it's a creature card that costs less than the last spell you cast this turn, you may put it onto the battlefield. Otherwise, draw a card.
[–7]: Target creature becomes a legendary 20/20 green creature named Illusion of Kaur with hexproof and trample until end of turn.