msem-instigator

Deathtouch
When Pestilent Scavenger enters, you may mill three cards.

When Petal Scatterer enters, create a green Aura enchantment token named Blossom attached to target land. It has enchant land and “Enchanted land has ‘{T}: Add {G}{G}.'”
Petal Scatterer gets +1/+1 for each noncreature, nonland permanent you control.

First strike
When Petal of a Heart enters, if you cast it, reveal up to two permanent cards with mana value 1 from your hand. For each card revealed this way, conjure a duplicate of that card into your hand.

Deathtouch, lifelink
Improve {1}{W/B} ({1}{W/B}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
{4}: Target creature gains deathtouch and lifelink until end of turn. Activate only during a player's first main phase.

Colossal 2—{1}{G}{G} (You may cast this for its colossal cost to have it enter with two +1/+1 counters; or pay {1}{G}{G} as a sorcery: Put two +1/+1 counters on it if it has none.)
Whenever a permanent you control with a counter on it becomes the target of a spell or ability an opponent controls, draw a card.

Flying
Whenever Phantasmal Owl attacks, it gets +1/+1 until end of turn for each other creature you control with flying.

Deathtouch
Whenever Phantasmal Stalker deals damage to a planeswalker, destroy it.

When Phantom Threader enters, create a white Aura enchantment token named Spectral Whispers attached to target creature. The token has enchant creature and “Enchanted creature has double strike as long as you control it. Otherwise, it can't attack or block.”

When Phasmopillar enters, search your library for a creature card with mana value 5 or greater, reveal it, put it into your hand, then shuffle. If a creature card with mana value 9 or greater was revealed this way, put two +1/+1 counters on Phasmopillar.

Whenever a creature you control dies, draw a card if it had power greater than its base power.

{R}: Phyrexian Firemaster gains haste until end of turn.

Double strike, menace
{R}{W}, Exile Picturesque Champion from your graveyard: Target creature you control gains double strike and menace until end of turn. Activate only as a sorcery.

Lifelink

Whenever you cast a red spell, target creature gets +1/+0 and gains haste until end of turn.

{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.

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

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.

{T}, Tap an untapped creature you control: You gain 2 life.

Whenever Playful Surveyor attacks, reveal the top card of your library. If that card shares a color with a permanent you control, you gain 2 life.

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)
Trample

{T}: Plucky Pickpocket voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)
Whenever Plucky Pickpocket phases in, draw a card, then discard a card.

Deathtouch

{T}, Exile a land card from your hand, from your graveyard, or a land that you control: Add one mana of any color.

When Polgek Artisan enters, create an X/X colorless Juggernaut artifact creature token, where X is the number of artifacts and enchantments you control.

Whenever Polgek Songcrafter attacks, other attacking creatures you control get +1/+0 until end of turn. If you control five or more attacking creatures, choose up to one target creature the defending player controls. That creature can't block this turn.