msem-instigator

Parish Paragon gets +1/+1 for each creature you control.
All damage that would be dealt to other creatures you control not named Parish Paragon is dealt to Parish Paragon instead.

Tithe (As you cast this spell, you may tap three artifacts and/or creatures you control.)
Tap target creature. If this spell's tithe was paid, exile that creature.

As long as your deck contains only white and colorless cards, your minimum deck size is reduced by eight.

Creatures your opponents control enter tapped.
{7}{W}: Tap all creatures target player controls.

When Parrying Scholar enters, target creature gets +0/+3 until end of turn.

Enchant opponent
When Pathless Shallows enters, exile target creature enchanted player controls until Pathless Shallows leaves the battlefield.
Enchanted player can't cast spells with the same name as the exiled card.

Defender
Ascend {1}{W}{W} ({1}{W}{W}: Exile this creature, then return it to the battlefield transformed. Ascend only as a sorcery.)

Whenever Patron of Asham attacks, tap target creature an opponent controls with power less than or equal to your fealty to Plains. (Each Plains you control counts towards your fealty to Plains.)

(Add a quest counter as this enters. Sacrifice after 3.)
Once each turn, when you cast a creature spell, you may add a quest counter.
Return up to X target creatures you control to their owner's hand, where X is the number of quest counters on Paw Valley Expedition.
Create a 1/2 white Bear Monk creature token with vigilance and a 2/1 white Bear Knight creature token with first strike.

Enchant creature
Creatures blocking or blocked by enchanted creature have lifelink.

Tap target creature. You gain life equal to its toughness.

Flying, lifelink

Choose one —
• Counter target noncreature spell.
• Peer into the Cosmos deals 3 damage to target creature.
• Until end of turn, damage that would reduce your life total to less than 1 reduces it to 1 instead.
Monument {1}{U}{R}{W} (You may cast this transformed from your graveyard for its monument cost. Exile it if it would leave the battlefield or not resolve.)

Double strike

Whenever Pelaski Valiant becomes tapped, target creature gets +1/+1 until end of turn.

When Pensive Muse enters, create a white Aura enchantment token named Seal's Love attached to target creature you control. The token has enchant creature and “Enchanted creatures you control get +1/+1.”

Flying
When Percy's Messenger enters, you gain 2 life. You may put a lore counter on a Saga you control.

When Percy's Perfect World enters, search your library for a legendary white card, reveal it, put it into your hand, then shuffle.
If an effect would create one or more creature tokens under your control, it creates twice that many of those tokens instead.

Green creatures you control have “{T}: Add one mana of any color.”
Red creatures you control have “{1}, {T}: This creature deals 1 damage to target player.”
White creatures you control have “{2}, {T}: Tap target nonland permanent.”

Protection from tokens
[+1]: Each player may draw a card. For each opponent that does, you gain 1 life and create a 1/1 colorless Construct Actor creature token
[–2]: Each player sacrifices a creature. Create a token that's a copy of a creature sacrificed this way.
[–7]: Until end of turn, each creature you control becomes a 6/6 black Horror creature with trample, menace, and lifelink.

Whenever Perfecting Forgemaster enters or attacks, you may sacrifice an artifact. If you do, look at the top six cards of your library. You may reveal an Equipment card from among them. Put it onto the battlefield if its mana value is less than or equal to the sacrificed artifact's mana value. Otherwise, put it into your hand. Then shuffle.

First strike
Prevent all damage that would be dealt to creatures you control by sources with greater mana value.
{2}{W}{W}: Create a 1/1 colorless Construct Actor creature token. Put a vigilance counter on it.

{2}, {T}: You gain life equal to the number of colors among cards in your graveyard.
{W}{U}{B}{R}{G}: Transform Performer of Enlightenment.

When Performers of Purpose enters, if a permanent you controlled left the battlefield this turn, create a 1/1 colorless Construct Actor creature token.
As long as it's your turn, Performers of Purpose has first strike.

Perish Song enters with three time counters on it.
At the beginning of your upkeep, remove a time counter from Perish Song. Then if it has no time counters on it, sacrifice it and destroy all creatures.