msem-instigator

Flying
When Sharp-Eyed Wingmate enters, you may return target creature to its owner's hand.

Vanguard — Whenever a creature you control attacks alone, Shocking Ewe deals 2 damage to defending player.

Haste
Whenever you sacrifice another permanent, put a +1/+1 counter on Shrine Razer.

When Sigiled Bulwark enters, search your library for a creature card and a noncreature card and reveal them. An opponent chooses one of those cards. Shuffle the chosen card into your library, then put the rest into your hand.

As Silent Hypnotist enters, choose a noncreature card name.
Spells with the chosen name can't be cast.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Whenever an opponent is dealt damage by one or more sources you control for the second time each turn, draw a card.

Whenever a player casts an instant or sorcery spell from their hand, you may exile that card as it resolves instead of putting it anywhere else.
Whenever Skill Sketcher attacks, you may cast a card exiled with it. That spell costs {X} less to cast, where X is Skill Sketcher's power.

Enchant creature
Enchanted creature gets +1/+1 and has flying.
When Skypath Pilgrimage enters, journey twice. (Exile the top two cards of your library face up. Whenever a creature you control deals combat damage to an opponent, put a journeyed card you own into your hand.)

Haste
Whenever a creature attacks, Slashing Pangolin gets +1/+1 until end of turn.

Vanguard — Whenever a creature you control attacks alone, target creature can't block this turn.

Vanguard — Whenever a creature you control attacks alone, it gets +1/+1 until end of turn. Untap that creature.

Vanguard — Whenever a creature you control attacks alone, you may exile target instant or sorcery card from your graveyard. If you do, you may cast that spell from exile until your next turn. If that spell would be put into a graveyard, exile it instead.

Sludge-Gill Fox can't be blocked as long as it's attacking alone.
Whenever Sludge-Gill Fox deals combat damage to a player, you may draw a card.

Defender
Whenever Slumbering Bear is dealt damage, put a +1/+1 counter on it.
Remove a +1/+1 counter from Slumbering Bear: It can attack as though it didn't have defender this turn.

Target creature can't block this turn. Smokescreen deals 2 damage to that creature's controller.

Scry 2 if a player lost life this turn. You draw two cards and you lose 2 life.

Trample
When Spikehorn Behemoth leaves the battlefield or phases out, draw a card.

Whenever Sporecaster or another Insect you control enters, each opponent loses 1 life.

When Sporecrowned Scavenger enters, target opponent loses life equal to the number of Insects you control and you gain that much life.

Haste
Whenever Spotted Slugger deals combat damage to a player, you may have it deal damage equal to its power to target creature.

Experience (Whenever this creature attacks, if it has fewer than three +1/+1 counters on it, put a +1/+1 counter on it.)
Whenever a +1/+1 counter is put on a creature you control, target creature gains trample until end of turn.

Whenever Starlight Emissary harnesses a spell, draw a card.

Flying
Vanguard — Whenever a creature you control attacks alone, you may put a +1/+1 counter on it.

({T}: Add {W} or {U}.)
Still Waters enters tapped unless you control two or more basic lands.

Flying
Whenever Stingsower attacks, you may pay {3}{B}{B}. If you do, target creature gets -1/-1 for each Insect you control until end of turn.