msem-instigator

You may exile cards you own as you reveal them. (You see the card before you exile it.)
During each of your turns, you may cast a card exiled with Starwing Nebula.

Choose one —
• Destroy target artifact or land.
• State Collapse deals damage equal to the number of artifacts you control to any target.

Whenever Stealer of Secrets deals combat damage to a player, draw a card.

Prowess
Whenever Steamwalker attacks, you may discard a card. If you do, draw a card, then catalyze. (The next spell you cast this turn costs {1} less to cast.)

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

Flash
Advance {3}{W} (Cast this for {3}{W} to advance it as it enters. {3}{W}: Advance this as a sorcery.)
Whenever Steelwoven Soldier advances, it gets +2/+2 until end of turn.

Whenever Steward of Silence blocks, you get a glory counter. (You lose glory counters before life. A player with ten or more glory counters wins the game.)

Target opponent discards a card at random. If that card's mana value is 3 or less, you may cast it without paying its mana cost.

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

Whenever you cast a spell that doesn't share a color with Stinging Hunter, each opponent loses 1 life.

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.

Until end of turn, gain control of target artifact or land and it gains haste. Untap it.
Create a Gold token. (It's an artifact with “Sacrifice this artifact: Add one mana of any color.”)

{1}, {T}, Sacrifice Stolen Strain: Target creature gains lifelink until end of tun.
{1}, {T}, Sacrifice Stolen Strain: Target creature gains winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)

Haste
Storm Entity enters the battlefield with a +1/+1 counter on it for each other spell cast this turn.

Whenever a permanent you control becomes tapped, Storm Servant gets +1/+1 until end of turn.

Flying, haste
Whenever you cast an instant or sorcery spell, create a token that's a copy of Stormcall Thunderbird.

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.)

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

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

Street Busker gets +2/+0 as long as you've gained life this turn.

When Street Stalker enters the battlefield, target opponent loses 1 life for each creature you control named Street Stalker.

Whenever you make first contact, target creature you control can't be blocked by Humans this turn. (You make first contact the first time each turn you cast a spell with a name not in your graveyard or control already.)

Enchant creature
Enchanted creature gets +1/+0 and can't be blocked by creatures with greater mana values.

Striptide deals 1 damage to target creature. Unattach all artifacts from it. It becomes red until end of turn.
Draw a card.