msem-instigator

When Polluted Servant enters, target opponent loses 1 life and you gain 1 life.
{2}{U}: Exile Polluted Servant, then return it to the battlefield tapped under your control.

Inspired — Whenever Pon's Apprentice becomes untapped, target creature you control has base power and toughness 5/5 until end of turn.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you cast an instant or sorcery spell, up to one other target creature has base power and toughness 0/2 until end of turn.

Whenever you cast a spell that doesn't share a color with Pond Tenders, you may put target card from your graveyard on the bottom of your library.

Whenever a player cycles a card, Possibility Grinder gets +2/+2 until end of turn.

When Powercell Cultivator enters, create a tapped colorless Powercell artifact token with “{T}: Add {C}.”
Artifacts you control have “{T}: Add one mana of any color.”

Whenever Practical Battlemage attacks, catalyze. (The next spell you cast this turn costs {1} less to cast.)

Predatory Abomination has deathtouch and lifelink as long as you control another Horror.

Flash
When Pride of Thorns enters, it gets +3/+3 until end of turn.

As an additional cost to cast this spell, pay {2} or reveal an instant or sorcery card from your hand.

{T}: Add {C}.
Whenever you tap Primal Channeler for mana, the next creature spell you cast this turn can be cast as though it had flash.

When Primordial Progenitor dies, create two 1/1 red Elemental creature tokens.

When Prismatic Basilisk enters, you may search your library for a permanent card with mana value 1 or less, reveal it, put it into your hand, then shuffle.
{2/W}{2/U}{2/B}{2/R}{2/G}: Prismatic Basilisk gets +5/+5 and gains flying until end of turn.

Lifelink
Heretic (Whenever you cast a spell that doesn't share a color with this creature, it gets +1/+1 until end of turn.)

Flying
{3}: Prismscale Dragon gets +1/+1 until end of turn for each color of mana spent to activate this ability.

Defender
Whenever you cast an enchantment, instant, or sorcery spell, scry 1 if it's the first time this ability has resolved this turn. If it's the second time, Prismscale Piranhas can attack this turn as though it didn't have defender. If it's the third time, whenever Prismscale Piranhas deals combat damage to a player this turn, draw a card.

When Prized Holsteins enters, create a 2/2 white Dwarf creature token.
When Prized Holsteins leaves the battlefield, you gain 2 life.

Profane Emissary gets +2/+2 and has lifelink as long as you control a Demon.
If you would draw a card, you may instead search your library for a Demon card, reveal it, put it into your hand, then shuffle. You lose life equal to that card's mana value.

When Profaner of Souls enters, you may return target creature card with mana value 2 or less from your graveyard to the battlefield.
Revive {6}{B} ({6}{B}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Whenever another nontoken creature you control enters, if it has a different name than each other creature you control and card in your graveyard, you may create a token that's a copy of it.

Whenever Professor's Assistant becomes tapped, add {R}. Until end of turn, you don't lose this mana as steps and phases end.

Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
Morph {1}{G} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

As long as another creature you control is attacking, Prolific Thief can't be blocked.
Whenever Prolific Thief deals combat damage to a player, draw a card, then discard a card.

Whenever you cast a spell from exile, Promised Seeker gets +3/+3 until end of turn.
Prophecy {G} (Once each turn, you may exile a card with prophecy as you reveal it. When you do, you may cast it for its prophecy cost as long as it's exiled.)

{1}{W}, {T}, Sacrifice Prophet of Pacifism: Prevent all damage that would be dealt to players this turn.
Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)