msem-instigator

Flying, first strike
Whenever this creature transforms into Flame-Tested Dragon or attacks, it deals 1 damage to each creature you don't control.

As an additional cost to cast this spell, exile a creature card from your graveyard.

Hexproof
Whenever you cast a spell with mana value 5 or greater, each opponent discards a card and loses 3 life.

Vigilance
Warriors you control have ward {X}, where X is the number of Warriors you control. (Whenever this creature becomes the target of a spell or ability an opponent controls, counter it unless that player pays {X}.)

Frondpond Prankster can't be blocked.
Whenever Frondpond Prankster enters or deals combat damage to a player, target player reveals their hand, then you choose any number of nonland cards from it. That player puts those cards on the bottom of their library in a random order, then draws that many cards.

Untap all permanents you control.
Coalesce {5}{G}{U} (You may cast this from your graveyard for {5}{G}{U}. If you do, it enters as a Horror creature after it resolves. Exile it if it would leave the battlefield or not resolve.)
{G}{U}: Untap Fulfill Twisted Dreams.

Flying
Whenever you cast a creature spell, creatures you control get +1/+1 until end of turn.
Whenever you cast a noncreature spell, create a 2/2 red and white Cat Knight creature token.

Wither (This deals damage to creatures in the form of -1/-1 counters.)

Trample
Cycling {2} ({2}, Discard this card: Draw a card.)

Whenever a creature attacks, if its toughness is greater than its power, untap it.

Trample
When Ghastly Progenitor enters, each opponent reveals their hand. Choose two nonland cards revealed this way. Their owners discard those cards.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)

As you harmonize, you may choose another harmony ability to trigger. (They can't be the same harmony.)
Harmony — Scry 1.

Haste
When Gilded Gearhulk enters, you may destroy target noncreature, nonland permanent.

Defender
When Glacial Buttress dies, tap each creature that dealt damage to it this turn. Those creatures don't untap during their controller's next untap step.

Flying
{3}{R}{R}: Untap all creatures you control. After this main phase, there is an additional combat phase followed by an additional main phase. Activate only any time you could cast a sorcery.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)
Cycling {B} ({B}, Discard this card: Draw a card.)

Concord — When Gold Pelt Responders enters, if there are four or more card types among permanents you control, you may exile target nonland permanent an opponent controls with mana value 4 or less until Gold Pelt Responders leaves the battlefield.

{1}, {T}, Move a -1/-1 counter from another creature onto Grace of the Trinity: Another target creature gains indestructible until end of turn.

Flying, trample, haste
Dragons you control get +3/+3 as long as you control permanents with total mana value 20 or greater.
Whenever you spend five or more mana to cast a spell or activate an ability, create a 2/2 red Dragon creature token with flying.

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Sacrifice another creature: Grotesque Defiler gains flying until end of turn.
Whenever Grotesque Defiler deals combat damage to a player, if you're in a renaissance, that player discards a card.

Flying, haste
Whenever Guardian of the Devout attacks or blocks, other creatures you control gain indestructible until end of turn.

Hexproof, trample
Whenever Gui, the Islandbringer deals combat damage to an opponent, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.

When Gulch Custodian enters, return an artifact you control to its owner's hand.