msem-instigator

You may shuffle your graveyard into your library. Draw X cards.
Flashback {X}{U}{U}{U}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Creature spells cost {1} more to cast.
At the beginning of your upkeep, put a decay counter on Stonewood Sanctuary. Then if it has three or more decay counters on it, sacrifice it.

Choose one. If an opponent lost 3 or more life this turn, choose any number instead.
• Target player sacrifices a legendary creature.
• Target player reveals their hand. You choose a nonland card from it. That player discards that card.
• Exile target player's graveyard.

While an opponent is choosing targets as part of casting a spell they control or activating an ability they control, that player must choose at least one Flagbearer on the battlefield if able.
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.)

Whenever Backstreet Gutter-Runner attacks, if you control another Pirate or Rogue, it deals 2 damage to each opponent.

Haste
Augmented — When Attuned Lifeform enters, if you've spent {W}{U}{B}{R}{G} to cast spells this turn, put a +1/+1 counter on each creature you control. They gain vigilance until end of turn.

You may play cards you own from outside the game.

Whenever one or more creatures you control deal combat damage to a player or planeswalker, you draw a card and you lose 1 life.

Create three 2/2 green Wolf creature tokens.

{B}, {T}: Destroy target tapped creature.

Once each turn, when you activate a nonmana ability, you may tap target creature.
{1}{U}: Foggy Town Militia gains flying until end of turn.

Creatures can't attack or block alone.

Heroic — Whenever you cast a spell that targets Halcyon Hoplite, Halcyon Hoplite gains flying until end of turn.
When Halcyon Hoplite dies, if it was enchanted, create a 1/1 white Bird creature token with flying.

You may cast this spell as though it had flash if you pay an additional {2} to cast it.
You may have Resourceful Impersonator enter as a copy of any creature on the battlefield.

Enchant creature
Enchanted creature and other creatures you control that share a creature type with it get +1/+1 and have vigilance.

When Thoughtgrinder enters, each player discards a card.
Unearth {1}{U}{B} ({1}{U}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the end step or if it would leave the battlefield. Unearth only as a sorcery.)

Whenever Valinov Collector or another artifact you control enters, Valinov Collector deals 2 damage to each opponent and you gain 2 life.

Draw two cards, then create an X/X white Illusion creature token, where X is the number of cards you've drawn this turn.

Search your library for a Dragon card, reveal it, put it into your hand, then shuffle. It deals damage equal to its power to you.

Until end of turn, creatures you control gain “When this creature dies, return a noncreature card from your graveyard to your hand.”

Whenever Portal Inhibitor attacks, exile target nonland card from defending player's graveyard. Copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)

When Astute Sceneweaver enters, proliferate. (Choose any number of permanents and/or players with counters on them, then give each another counter of each kind already there.)

When Golden Grizzly enters, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)

Whenever a creature you control leaves the battlefield, if it had counters on it, you may put one of those counters on Ironpact Marauder.
{1}{B}, Remove two counters from Ironpact Marauder: You draw a card and you lose 1 life.

When Sheltered Diviner enters, each player mills three cards.