msem-instigator

Flying, vigilance, indestructible
Faradia, Honored Sovereign can't attack or block unless you tap three other untapped creatures and/or artifacts you control.

Target creature gets +1/+0 and gains first strike and haste until end of turn.

When Festival Rioters enters the battlefield, create a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”
{1}{R}: Festival Rioters gets +2/+0 until end of turn.

Harmony — Create a 1/1 white Bird creature token with flying.
{4}: Harmonize. (Trigger up to one harmony of one permanent you control.)

Equipped creature gets +2/+2.
Equip {3}

Any number of target creatures you control each fight target creature with power 3 or greater. (All fight damage happens simultaneously.)

When Fungal Whomper enters the battlefield, you gain 4 life.
When Fungal Whomper leaves the battlefield, germinate four times. (To germinate, put a +1/+1 counter on a creature or create a 1/1 green Saproling creature token.)

Gathering Beacon enters the battlefield tapped.
{T}: Add {G}.
{2}, {T}, Sacrifice Gathering Beacon: Choose a creature or planeswalker type, then reveal the top five cards of your library. You may put a card of the chosen type into your hand, then put the rest on the bottom in any order.

Creatures you control get +1/+1 and gain trample and lifelink until end of turn.

As an additional cost to cast this spell, discard a card.
Draw two cards. Gift of the Phoenix deals 2 damage to you.

{T}: Add three mana of any one color.

Harmony — Target creature gains flying until end of turn.
When Glamorous Aerialist enters the battlefield, harmonize. (Trigger up to one harmony of one permanent you control.)

When Glamorous Festivities enters the battlefield or at the beginning of your upkeep, you may put two +1/+1 counters on each creature you control. If you do, each opponent may put a +1/+1 counter on each creature they control.

Lifelink (Damage dealt by this creature also causes you to gain that much life.)

Flying
When Greater Swooprat enters the battlefield, creatures your opponents control get -1/-1 until end of turn.

When Grim Festivities enters the battlefield or at beginning of your upkeep, you may return a creature card from your graveyard to the battlefield under your control. If you do, each opponent may return a creature card from their graveyard to their hand.

Sacrifice another creature: Grindlesnap gets +3/+2 and gains trample until end of turn if that creature was a Crocodile. Otherwise, it gets +1/+1 until end of turn.
Whenever Grindlesnap is dealt combat damage, create a 3/2 green Crocodile creature token with trample.

Enchant opponent
When Grisly Hunger enters the battlefield, enchanted player's life total becomes 10.
At the beginning of enchanted player's end step, they sacrifice a creature. If they do, they lose life equal to that creature's power.

Sacrifice another creature: Grisly Rougarou deals damage equal to the sacrificed creature's power to any target.

Untap target creature. It gets +1/+3 until end of turn.

Tithe (As you cast this spell, you may tap three artifacts and/or creatures you control.)
Creatures you control gain indestructible until end of turn. If this spell's tithe was paid, put a +1/+1 counter on each creature you control.

[+1]: Create a 1/1 red Cleric creature token. If you control three or more Clerics, you may instead create Aspect of Faradia, a legendary 5/5 white Angel creature token with flying and vigilance.
[–1]: Exile target creature if you control an Angel. Otherwise, that creature can't attack or block and its activated abilities can't be activated until your next turn.
[–7]: Creatures you control get +5/+5 and gain flying and vigilance until end of turn.

Flying, haste
Whenever you attack with three or more creatures, harmonize three times. (To harmonize, trigger up to one harmony of a permanent you control.)
If you would harmonize, you may instead return Herald of Festivities from your graveyard to your hand.

Lifelink
Tap three other untapped creatures and/or artifacts you control: Transform Heroic Crusader.