msem-instigator

Flying
Stormcloud Drake gets +1/+0 for each instant and sorcery card in your graveyard.
Whenever Stormcloud Drake attacks, tap target creature defending player controls.

Vigilance
{4}{U}: Draw a card.

Prowess, haste

Stormsurge deals 3 damage to any target.
Orchestrate {R} (You may exile this card from your hand anytime you could cast a sorcery for its orchestrate cost. When you next resolve a spell, you may cast this from exile without paying its mana cost.)

Whenever one or more creatures you control deal combat damage to a player, exile a nonland card from that player's graveyard. Copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)

{1}, {T}: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
{2}, {T}, Exile an instant or sorcery card from your graveyard: Stormvolt Apprentice deals 1 damage to each opponent.

Draw a card. Then you may cast an instant spell with mana value 2 or less from your hand without paying its mana cost.

Flying
Prophecy {0} (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.)

At the beginning of your upkeep, mill two cards.
{1}{G}, Sacrifice Strange Discovery: Return target card from your graveyard to your hand.

Flash
Flying
When Strange Sights dies, investigate. (Create a colorless Clue artifact token with “{2}, Sacrifice this artifact: Draw a card.”)

Enchant opponent
At the beginning of enchanted player's upkeep, they mill two cards.
{U}, Sacrifice Strange Tides: Shuffle up to four target cards from your graveyard into your library.

Target creature gets -3/-3 until end of turn.

Target creature gets -2/-2 until end of turn. If you control two or more Deserts, destroy that creature instead.

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Target creature gets +2/+2 until end of turn. Untap it.

Stratospheric Bombardment deals X damage to any target and you gain that much life.

Flying
When Stratusform Seraph enters, you may return target creature you control to its owner's hand.

Prowess
Pay 2 life: Change a target of target spell or ability to Straw Intellectual.

Creatures blocking or blocked by Straw Officer have wither. (They deal damage to creatures in the form of -1/-1 counters.)

As Straw Simulacrum enters, choose a creature type.
Straw Simulacrum is the chosen creature type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Whenever another creature you control enters, put your choice of a +1/+1 counter, a trample counter, or a haste counter on it.

Stray Sighthound can't be blocked by creatures with power 2 or less.
Attain {3}{G} ({3}{G}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

Each player chooses one card in their hand, then discards the rest.

Target player gains X life.