msem-instigator

When Frantic Efreetspeaker enters, you may discard a card. If you do, draw a card.
{2}, Exile Frantic Efreetspeaker from your graveyard: Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Menace
When Marrow Raptor enters, you may sacrifice a land or exile a land card from your graveyard. If you do, put a +1/+1 counter on it.

Whenever an opponent casts a noncreature spell, put a +1/+1 counter on target creature you control.

Haste
Augmented — When Attuned Lifeform enters, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, put a +1/+1 counter on each creature you control. They gain vigilance until end of turn.

Draw two cards, then you may put a land card from your hand onto the battlefield. If you cast In Dire Straits during your turn for its reconstruct cost, create X 3/2 green Horror creature tokens, where X is the number of lands you control.
Reconstruct {8}{G}{G}{U}{U} (You may cast this from your graveyard for its reconstruct cost reduced by the mana value of a permanent you sacrifice as you cast it this way. Then exile this.)

As an additional cost to cast this spell, sacrifice a creature.
Create a 5/5 black Demon creature token with flying. You lose 2 life.

When Sewer Dweller enters or dies, create a 1/1 black Rat creature token with “This creature can't block.”

Detain target creature. (Until your next turn, that creature can't attack or block and its activated abilities can't be activated.)
Scry 1.

Destroy target creature. Create a tapped 2/2 black Zombie creature token.

Choose two —
• The next time a triggered ability of a permanent you control would trigger this turn, that ability triggers an additional time.
• Create a token that's a copy of a creature you control.
• Search your library for a creature card with mana value 2 or less, put it onto the battlefield, then shuffle.
• Sacrifice a creature. If you do, draw two cards.

You draw two cards, lose 2 life, and mill two cards.

Equipped creature gets +1/+0, has no name, and loses all non-Pirate, non-Rogue creature types.
{1}: Equipped creature gains the creature types and activated abilities of target creature and its name becomes that creature's name until end of turn.
Equip {1}

({T}: Add {G}.)
Moon of the Promised Day enters tapped.
{1}{G}, {T}: Scry 1.

Permanents you control with mana value 1 or less have first strike, haste, and lifelink.

Whenever Caldera Crawlers attacks, you may sacrifice a land or exile a land card from your graveyard. If you do, target creature gets +1/+1 and gains menace until end of turn.

Flying
When Inspirational Beacon enters, you gain 3 life.

Whenever Yri, the Daring Blade and exactly one other creature attack, Yri and that creature can't be blocked by creatures with mana value 3 or less this turn.

Trample
Respawn (When this creature dies, if it attacked this turn, return it to its owner's hand.)

Once each turn, when a player casts a spell, you may choose two target players. Each of those players exiles cards from the top of their library until they exile a nonland card with mana value less than that spell's. They may cast those cards without paying their mana cost. Then they put the rest of the exiled cards on the bottom of their library in a random order. (The active player puts their spell on the stack first.)

{T}: Add one mana of any color. Each other player adds one mana of any color at the beginning of their next first main phase.

When Hollow Hooligan enters, up to two target creatures can't block this turn.
Mirage {1}{R} (You may cast this spell as though it had flash for its mirage cost. If you do, sacrifice it at the beginning of the next cleanup step.)

Flash
When Olten Vipermoa enters, you may return another creature you control to its owner's hand. If you do, put two +1/+1 counters on Olten Vipermoa.

Draw three cards, then you may submerge a card from your hand. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

Choose target creature, then choose two —
• The chosen creature gets +3/+0 until end of turn.
• The chosen creature gains trample until end of turn.
• The chosen creature gains first strike until end of turn.

Enchant creature
Enchanted creature gains +X/+X, where X is your life total.
When enchanted creature dies, shuffle Life's Will into its owner's library.