msem-instigator

The next creature spell you cast this turn may be cast as though it had flash and costs {1} less to cast. If it entering the battlefield causes a triggered ability of it to trigger, that ability triggers an additional time.

Creatures with power 4 or greater can't attack or block unless their controller pays {2} for each of those creatures.

Hexproof from enchantments (This creature can't be the target of enchantment spells or abilities your opponents control.)

Harmony — Creatures you control gain double strike until end of turn.
When Twirling Duet enters, harmonize. (Trigger up to one harmony of one permanent you control.)

Escalate—Return another spell you control to its owner's hand. (Pay this cost for each mode chosen beyond the first.)
Choose one or both —
• Draw a card.
• Draw a card.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
Deathtouch

When Undying Watcher enters, germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)
Sacrifice another creature: Undying Watcher gains indestructible until end of turn.

{T}: Add one mana of any color.
{T}, Sacrifice Unicorn of the Vale: Add three mana of any one color.

({T}: Add {B} or {R}.)
As Vacated Bar enters, you may pay {1}. If you don't, Vacated Bar enters tapped.

All creatures get -X/-X until end of turn. X can't be 0.
Whenever a creature dies this turn, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Tithe (When this creature enters, you may tap three other artifacts and/or creatures you control.)
When Vindictive Abbot enters, you may have target creature get -1/-1 until end of turn. If Vindictive Abbot's tithe was paid, destroy that creature.

Target creature you control gains trample until end of turn. Whenever that creature deals damage to a player this turn, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Draw X cards. Then if X is 2 or greater, you may discard any number of cards. For each card discarded this way, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

Tithe (When this creature enters, you may tap three other artifacts and/or creatures you control.)
When Wailing Chorus enters, each opponent discards a card. If its tithe was paid, each opponent discards two cards instead.

Germinate three times. You lose 3 life. (To germinate, put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Escalate {B} (Pay this cost for each mode chosen beyond the first.)
Choose one or more —
• Wicked Blow deals 3 damage to target player or planeswalker.
• Wicked Blow deals 3 damage to target creature.
• You gain 3 life.

When Wild Festivities enters or at the beginning of your upkeep, you may put a creature card from your hand onto the battlefield. If you do, each opponent creates a 1/1 blue Frog creature token.

Target creature you control gets +2/+2 until end of turn. It fights target creature an opponent controls.

Enspirit (As you cast this spell, you may exile a nonenchantment creature you control until this leaves the battlefield or fails to resolve. Reduce this spell's cost by the exiled card's mana value.)
You may have Witch of Shifting Waters enter as a copy of any creature on the battlefield, except it's an enchantment in addition to its other types.

Flash
When Witch's Invocation enters, draw a card.
You may cast spells as though they had flash.

Whenever Withering Husk enters or attacks, you may discard a card and pay 1 life. If you do, draw a card, then each opponent loses 1 life.
Recite {R} (You may cast this creature from your graveyard for its recite cost. If you do, exile it when it enters or if it would leave the battlefield.)

When Woopip Bruiser enters, germinate. When you do, you may have target non-Fungus creature get -X/-X until end of turn, where X is the greatest power among creatures you control. (To germinate, put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Harmony — Germinate. (Put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)
When Woopip Chef enters, harmonize. (Trigger up to one harmony of one permanent you control.)