msem-instigator

Counter target spell unless its controller pays {1}.
Metamorph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

Defender
{1}{U}: Sea Wall gets +0/+1 until end of turn.
Whenever Sea Wall perseveres, you may return target creature an opponent controls to its owner's hand. (A creature perseveres when it survives damage.)

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast a noncreature spell, 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.”)

Create a token that's a copy of target creature.
Metamorph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

Counter target spell. If you control a Wizard, scry 2. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Counter three target spells.

At the beginning of your end step, put a flood counter on Swelling Sea, then return each nonland permanent with mana value less than or equal to the number of flood counters on Swelling Sea to its owner's hand.

Scry 3. If you control a Wizard, draw a card.

Whenever Wadepool Frog attacks, it gains flying until end of turn.

Counter target activated or triggered ability.
Metamorph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

Flying

When Woken Wave dies, you may exile it. If you do, return target card from your graveyard to the battlefield face down.

Whenever Anima Interrogator attacks, defending player reveals a card at random from their hand.

Whenever another Zombie or Demon creature enters the battlefield under your control, 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.”)

Choose one or both—
• Target creature has base toughness 1 until end of turn.
• Remove all but one loyalty counter from target planeswalker.

Lifelink
Whenever you sacrifice a nonland permanent, you may pay {1}. If you do, you draw a card and you lose 1 life.

{B}, {T}, Pay 1 life, Discard a card, Sacrifice Dark Rite Cultist and another creature: Create a 5/5 black Demon creature token with flying.

Target opponent discards a card. If a creature card was discarded this way, that player loses 3 life. If a land card was discarded this way, add {B}{B}. If a noncreature, nonland card was discarded this way, draw a card.

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

Target opponent loses 1 life for each creature they control. You gain 2 life for each Wizard you control.

All creatures get -2/-2 until end of turn.
Metamorph {1}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

Destroy target creature. If you control a Wizard, put up to one target creature card from your graveyard on top of your library.

When Gulch Glutton enters the battlefield, create a 1/1 black Rat creature token.
Whenever Gulch Glutton perseveres, each player sacrifices a creature. (A creature perseveres when it survives damage.)

Deathtouch
Whenever a creature an opponent owns dies, exile the top two cards of that player's library face down. For as long as those cards remain exiled, you may look at them, you may cast them, and you may spend mana as though it were mana of any type to cast them.

Target creature gets +3/-1 until end of turn.
Metamorph {1}{B} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)