msem-instigator

Whenever a creature attacks you or a planeswalker you control, Pitfall Pangolin gets +1/+0 until end of turn.

Flash
When Pivot-Fist Meditant enters, choose a creature you control. Whenever that creature is dealt damage this turn, it deals that much damage to any other target.

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

Flash
Flying
When Pixie Procurer enters, copy target activated ability, triggered ability, or spell with mana value 2 or less. You may choose new targets for the copy. (A copy of a permanent spell becomes a token.)

Enchant creature
Enchanted creature is a Horror with base power and toughness 3/3 and loses all other creature types and abilities.
Whenever enchanted creature deals combat damage to a creature, create a token that's a copy of Plagas Infestation and attach it to the damaged creature.

Deathtouch
Unveil {3}{B}{G} ({3}{B}{G}: Transform this. Unveil only as a sorcery.)

Other Zombies you control get +1/+1.
Whenever Plague Herald or another Zombie enters under your control, target creature you control gains deathtouch until end of turn.

Vigilance, deathtouch, menace

Equipped creature can't have -1/-1 counters put on it.
Equip {1}

Whenever you cast an instant or sorcery spell, each opponent loses 1 life.
Attain {3}{B} ({3}{B}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Whenever equipped creature attacks, each player loses 3 life.
Equip {2}

Planar Alignment enters tapped.
{T}: Add {C}.
{6}, {T}, Exile Planar Alignment: Search your library for a card, put it into your hand, then shuffle.

{B}, {T}, Sacrifice Planar Eulogist: Aetherize target creature card in a graveyard. (To aetherize, create a token that's a copy of it, then exile that token.)
{6}{B}: Aetherize target creature card in a graveyard.

Primal—{W}, Exile a creature you control. (During your turn, you may cast this spell by paying {W} and exiling a creature you control instead of playing a land.)
When Planar Eviction enters, exile another target nonland permanent until Planar Eviction leaves the battlefield.

{T}, Sacrifice a creature: Return target creature card from your graveyard to your hand.
{T}, Sacrifice an artifact: Planar Processor deals 1 damage to any target.
{T}, Sacrifice an enchantment: Draw a card.
{T}, Sacrifice a land: Add one mana of any color.

{T}: Add {C}. Put your choice of a flying, first strike, menace, trample, vigilance, or +1/+1 counter on Planar Rift.
{1}, {T}: Remove any number of counters from Planar Rift: Add {C} for each counter removed this way.
{T}: Move a counter from Planar Rift onto target creature you control. Activate only as a sorcery.

You may play cards you own from outside the game.

Whenever equipped creature deals combat damage to a player, draw a card.
Whenever a Vehicle you control becomes a creature, you may attach Planar Uplink to it.
Equip {U}

Flying
When Planchette Poltergeist enters, you may exile target creature. Its owner may cast it from exile for as long as it remains exiled.

When Plane-Traversal Guide enters, you may exile a card you own from outside the game. When Plane-Traversal Guide is no longer on the battlefield, put the exiled card into your hand.

Flying
Whenever Planetary Reconnoiterer attacks, target creature you control gains flying until end of turn.

Menace, haste
Whenever another player casts a spell that targets Plasma Addict, that player gains control of Plasma Addict.

First strike, haste
Whenever you cast an enchantment, instant, or sorcery spell, put a +1/+1 counter on Plasma Blader.
{2}{R}{R}, Sacrifice Plasma Blader: It deals damage equal to its power to any target.

Sunburst (This enters with a +1/+1 counter on it for each color of mana spent to cast it.)
Sacrifice another artifact: Put a +1/+1 counter on Plasma Enforcer.
When Plasma Enforcer dies, create a 1/1 colorless Servo artifact creature token for each +1/+1 counter on Plasma Enforcer.