msem-instigator

[+1]: Until your next turn, up to one target creature gets -9/-0.
[–2]: Reveal the top four cards of your library. Put any number of cards with mana abilities from among them into your hand, then put the rest on the bottom of your library in any order.
[–6]: You get an emblem with “At the beginning of each opponent's end step, gain control of target creature that player controls.”

Respawn (When this creature dies, if it attacked this turn, return it to its owner's hand.)
When Tutorial Boss enters, create a 1/1 blue Pirate creature token.

{T}: Add one mana of any color.

Whenever another creature you control enters, put a +1/+1 counter on each creature you control with lesser power or lesser toughness than that creature.

Flash (You may cast this spell any time you could cast an instant.)
{2}{G}: Luminescent Croaker gains indestructible until end of turn.

Whenever Fox of the Mushroom Forest enters or deals combat damage to a player, its activated abilities cost {W} less to activate until your next turn.
{W}, Sacrifice Fox of the Mushroom Forest: Counter target noncreature spell unless its controller pays {2}.

Enchant creature
When Sprawled Arming enters, put a +1/+1 counter on enchanted creature.
Enchanted creature has first strike.
{5}: Return Sprawled Arming to its owner's hand.

Art of war — At the beginning of your end step, if Kuryu Swordsman dealt damage to an opponent this turn, you may have Kuryu Swordsman fight target creature you don't control. (Each deals damage equal to its power to the other.)

Vigilance
Renown 1 (When this creature deals combat damage to a player, if it isn't renowned, put a +1/+1 counter on it and it becomes renowned.)
When Champion of Destinies becomes renowned, you become the monarch.

Vigilance
Whenever Cohorts of the Grove deals combat damage to a player, if you control a creature with power 4 or greater, draw a card.

When Blossom-Sower Witch enters, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)
Whenever you sacrifice a permanent, you gain 1 life.

{1}{W}, {T}: Tap target creature.
Put a -1/-1 counter on Insistent Ingenue: Untap Insistent Ingenue.

Foretell {1}{B}{B} (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.)
Choose one. If this spell was foretold, you may choose both instead —
• Each opponent reveals their hand. You choose a noncreature, nonland card revealed this way. Exile that card.
• Each opponent sacrifices a creature or planeswalker.

Tithe (When this creature enters, you may tap three other artifacts and/or creatures you control.)
When Cataclysmic Preacher's tithe is paid, return target instant or sorcery card from your graveyard to your hand.

Choose two —
• Return up to two target creature cards from your graveyard to your hand.
• Return up to two target enchantment cards from your graveyard to your hand.
• Return up to two target artifact cards from your graveyard to your hand.
• Target player may put a permanent card from their hand onto the battlefield.

When Journey through Uwaito enters, draw a card, then choose a creature card name.
Whenever a creature you control with the chosen name dies, each opponent discards a card.

Remove a -1/-1 counter from target creature. That creature gets +2/+2 until end of turn.

Savage Lands enters tapped.
{T}: Add {B}, {R}, or {G}.

When Duskling Stalker dies, if it didn't have any counters on it, return it to the battlefield with your choice of a deathtouch, lifelink, or +1/+1 counter on it.

Destroy all nonlegendary creatures.

Dreamscaper enters tapped with three stun counters on it. (If it would become untapped, remove a stun counter from it instead.)
Whenever you cast your second spell each turn, you may untap Dreamscaper or tap target creature.
Whenever Dreamscaper deals combat damage to a player, draw two cards.

Flying
Whenever you cast a spell, create a 1/1 blue Boar Dragon creature token with flying.

When Disciple of the Buried Glade leaves the battlefield, create a 3/3 green Elemental creature token.

{T}: Add one mana of any color.
{5}, {T}, Sacrifice Cosmic Chart: Search your library for a card, put it into your hand, then shuffle.

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Ghostly Hounds mentors a creature, that creature can't be blocked this turn.