msem-instigator

Flying
Whenever an opponent casts a spell, copy it. You may choose new targets for the copy.

At the beginning of combat on your turn, creatures you control gain your choice of trample, menace, haste, or +1/+0 until end of turn.

Target creature can't block this turn. Smokescreen deals 2 damage to that creature's controller.

When Lunar Vigil enters, draw a card, then scry 2.
If you would draw one or more cards, you may instead put a night counter on Lunar Vigil and draw that many cards minus one.
Sacrifice Lunar Vigil: Target player draws a card and adds {R} for each night counter on it.

{3}{G}: Seasoned Farmer gets +2/+2 until end of turn.

When Escorted Ambassador enters, create two 1/1 white Robot Soldier artifact creature tokens.
Whenever a nonland, nontoken permanent enters, exile it unless it was the first to enter under its controller's control this turn.

When Iekin's Portal enters, look at the top five cards of your library. Put one into your hand and the rest into your graveyard.
{1}{U}{U}: Transform Iekin's Portal. Activate only if your fealty to Islands is five or greater.

Trample
Whenever a noncreature permanent is put into a graveyard from the battlefield, put a +1/+1 counter on Ruinous Naga.

When Hitana's Implements enters, draw a card.
{1}, {T}: Add one mana of any color.
Augmented — At the beginning of each end step, if you've spent {W}{U}{B}{R}{G} on spells this turn, exile Hitana's Implements. If you do, create a 5/5 blue Horror creature token.

Enchant creature
Enchanted creature has poisonous 3. (Whenever that creature deals combat damage to a player, that player gets three poison counters.)

Flash
Whenever you cast a Tale, look at the top two cards of your library. Put one into your hand and the other back on top or into your graveyard.

Flash
Flying
When Mending Valkyrie enters, choose target permanent you own or permanent card with mana value 3 or less in your graveyard. You may return it to your hand.

Untap target creature you control. It gains hexproof until end of turn.

Flying
When Depraved Imp enters, if you control a legendary creature, put two +1/+1 counters on Depraved Imp.

Indestructible
As long as your devotion to blue is less than five, Thassa isn't a creature.
At the beginning of each combat, you may tap or untap another target nonland permanent.
{2}{U}: Create a 1/1 blue Merfolk Rogue creature token with “{T}: Draw a card, then discard a card.”

Mentor (Whenever this creature attacks, put a +1/+1 counter on target attacking creature with lesser power.)
Whenever Master of Ancient Ways mentors a creature, that creature gains double strike until end of turn.

{T}, Pay 1 life: Add {W}.
{6}{W}{W}{W}, Exile Rius, Temple of the Grandfather from your hand: Target player gains 20 life.

Vanguard — Whenever a creature you control attacks alone, put a +1/+1 counter on it.

Flying
Wanderlust — When Crest Skimmer enters, if you control four or more differently named lands, draw a card.

This spell costs {1} less to cast for each Desert you control.
When Crested Crustacean enters, return target permanent to its owner's hand.

{T}: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
At the beginning of combat on your turn, you may exile a creature card from your graveyard. When you do, target creature with the same power as the exiled card can't be blocked this turn.

Trial 3 (As you cast this spell, an opponent of your choice may pay 3 life. If they don't, they fail the trial.)
Target creature gets -1/-1 until end of turn. If that creature's controller failed the trial, it gets -4/-4 until end of turn instead.

Bronze Giant has trample as long as you control a token creature.

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.
Flashback {3}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

When Herd Matron enters, distribute two +1/+1 counters among one or two target creatures you control.