msem-instigator

Enchant creature
Whenever enchanted creature attacks, it gets +3/+3 and gains trample until end of turn.

Return target creature to its owner's hand. You may shuffle up to four target cards from your graveyard into your library.

Target creature gets -1/-1 until end of turn. Germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Counter target enchantment, instant, or sorcery spell. (Then exile this card. You may cast the creature later from exile.)

Put a +1/+1 counter on up to one target creature. (Then exile this card. You may play the land later from exile.)

First strike
When Mutilated Warrior enters, you may have it deal damage to each player equal to the number of Warriors you control.

Whenever Mysteries of Life enters or you create a token, choose one that hasn't been chosen this turn —
• You gain 2 life.
• Draw a card, then discard a card.
• You may tap or untap target permanent.

{X}, Exile Mysterious Coffer: Return all nonland permanents with mana value X or less to their owner's hands.

(As you complete a condition, decode it. After all are decoded, you solve the mystery and transform this.)
When Mystery of the Crashed Craft enters, create two 1/1 red Alien creature tokens with “This creature can't block.”
{MG}—You cast an instant spell.
{MG}—You cast a sorcery spell.

Whenever you cast a spell from exile, you may draw a card.
At the beginning of your upkeep, you may reveal the top card of your library.

When Mystic Seer enters, each player may scry 1.
{2}{U}: Draw a card, then discard a card.

Enchant creature
When Mystic's Mantle enters, draw a card.
Enchanted creature gets +1/+1.
Mirage {G} (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.)

When Naga Cultivator enters, you may put a land card from your hand onto the battlefield.

{T}, Discard a card: Draw a card.

When Naiad of the Glen enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
Naiad of the Glen has trample as long as it has a +1/+1 counter on it.

When Naive Apprentice enters, each player creates a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)
As long as an opponent controls an artifact, Naive Apprentice gets +2/+0.

Nameless Throng can't block.
{1}{B}, Exile an artifact or enchantment card from your graveyard: Return Nameless Throng from your graveyard to the battlefield.

Flying
Civilized — Whenever Namuzzar's Disciple attacks, if you control an artifact, a creature, and an enchantment, put a +1/+1 counter on Namuzzar's Disciple.

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Flying
{1}{U}: Demigod — Whenever a creature you control deals combat damage to a player or planeswalker this turn, draw a card.
{3}{U}{U}: God — Create an X/X blue Spirit creature token, where X is the number of cards in your hand. Put a flying counter on it.

As an additional cost to cast this spell, return a creature you control to its owner's hand.
You may put a creature card with mana value less than or equal to the returned creature's mana value from your hand onto the battlefield with a +1/+1 counter on it.

Trial 2 (As you cast this spell, an opponent of your choice may pay 2 life. If they don't, they fail the trial.)
When Nascent Adversary enters, if the trial was failed, it gains haste and first strike until end of turn.

Vigilance, deathtouch
Prevent all damage that would be dealt to Nataila, Raven's Repented while it's attacking or blocking alone.

Search your library for a permanent card that could produce {G}, reveal it, put it into your hand, then shuffle.

{G}, Exile a creature card from your graveyard: Put two +1/+1 counters on target creature.