msem-instigator

{U}{R}{W}, Discard a card named Sha'Iv, God of Order: Sha'Iv gains indestructible and becomes a God creature in addition to its other types.
Whenever Sha'Iv enters or attacks, choose target creature an opponent controls. Untap it, then tap each other creature that player controls. They don't untap during their controller's next untap step.

Shadow Ball deals 2 damage to target creature or planeswalker and 2 damage to its controller. You gain 2 life.

Target creature phases out. Its controller sacrifices a creature. (Treat the phased out creature and anything attached to it as though they don't exist until its controller's next turn.)

Flash
When Shadow Stalker enters, for each player, look at the top card of that player's library. You may have that player put that card into their graveyard.

When Shadowbinder Touka enters or attacks, exile up to one target creature card from a graveyard.
You may play creature cards exiled with Touka.
Sacrifice another creature: Add two mana in any combination of colors. You can't spend this mana to cast spells from your hand. If this mana is spent to cast a creature spell, that creature enters with a finality counter on it.

When Shadowstrider dies, create a 2/2 colorless Spirit creature token.

Draw two cards. You lose 2 life. Create a Treasure token. (It's an artifact with “{T}, Sacrifice this artifact: Add one mana of any color.”)

Discard your hand. Draw cards equal to the number of creatures that died this turn.

When Shambling Gutless enters, target player discards a card.

Shambling Hive power and toughness are each equal to the number of Insects you control.
Shambling Hive has vigilance as long as you control four or more Insects, and has trample as long as you control eight or more Insects.

Choose two —
• Each opponent sacrifices a creature with mana value 3 or less.
• Each opponent sacrifices an enchantment with mana value 3 or less.
• Exile each opponent's graveyard.
• You gain 3 life.

When Shara, Prime Geneticist enters, if X isn't 0, create two X/X green Mutant creature tokens.
[+1]: Surveil 2. At the beginning of your next end step, untap up to one permanent.
[–2]: Conjure a card named Test Run into your hand. (It's a sorcery that costs {X}{G} with “Create an X/X green Mutant creature token. Draw a card.”)
[–7]: Search your library for a card and put it into your hand. Repeat this process once for each token you control. Then shuffle.

{T}: Each player draws a card.

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Spell you cast cost {1} less to cast as long as it's not your turn.

Flash
Unveil {3}{B}{G} ({3}{B}{G}: Transform this. Unveil only as a sorcery.)

Destroy target creature if it has mana value 4 or greater. If Shatter Facade was cast from exile, destroy that creature if it has mana value 3 or less instead.
Orchestrate {B} (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.)

Equipped creature gets +1/+1.
Whenever equipped creature becomes the target of a spell or ability an opponent controls, you may return Shawl of Warding to its owner's hand. If you do, counter that spell or ability.
Equip {2}

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Whenever you casting a noncreature spell causes an ability of a creature you control to trigger, that creature gains your choice of first strike, haste, menace, or trample until end of turn.

Advance {4}{B} (Cast this for {4}{B} to advance it as it enters. {4}{B}: Advance this as a sorcery.)
Whenever Shearing Vampire advances, target player discards a card.

Assault {2}{R}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Shemesh assaults, other creatures you control get +2/+2 and gain trample until end of turn.

Revive—{B}, Discard a card. ({B}, Discard a card, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Whenever a land you control enters, you may tap target creature.

Transcend (Activate as a sorcery to gain the next type and a +1/+1 counter.)
Ward—Discard a card.
{B}{R}: Demigod — Draw a card, then discard a card. You may have each opponent sacrifice a nonland permanent with the same mana value as the discarded card.
{4}{B}{R}: God — Create two tokens that are copies of Shi Hou's back face.

Whenever Shianne's Guardian or another creature you control enters, you may pay {1}{R}{G}. When you do, that creature deals damage equal to its power to any target.