msem-instigator

Deathtouch
When Shadowed Apostle dies, draw a card.

({T}: Add {B}.)
Shadowed Slums enters tapped.
{B}, {T}, Reveal a black card from your hand: Target player loses 1 life.

Sacrifice Shadowfeeder: Target player loses 1 life and you gain 1 life.

When Shadowlurk enters, if a creature died this turn, put a +1/+1 counter on it.

{2}: Equipped creature phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.)
Equipped creature can't be blocked except by Rogues and is a Rogue in addition to its other types.
Equip {1}

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.”)

Whenever Shah's Caravan attacks, creatures you control get +1/+1 until end of turn. If you control three or more Satrapies, creatures you control can't be blocked by creatures with power 2 or less this turn.
Satrapycycling {2} ({2}, Discard this card: Search your library for a Satrapy card, reveal it, put it into your hand, then shuffle.)

Prevent all combat damage that would be dealt this turn.
Satrapycycling {2} ({2}, Discard this card: Search your library for a Satrapy card, reveal it, put it into your hand, then shuffle.)

Enchant creature
You control enchanted creature.
When Shahmaran's Captivation enters, untap enchanted creature. It gains haste until end of turn.

When Shaidostan Cryoforger enters, exile the top card of your library.
When Shaidostan Cryoforger dies, you may put the exiled card into your hand.

Kicker {1}{R} (You may pay an additional {1}{R} as you cast this spell.)
Shal'Draen's Rage deals 1 damage to each creature. If this spell was kicked, it deals 3 damage to each creature instead.

Shala's Immolation deals 5 damage to target creature and 2 damage to that creature's controller.

Haste
Whenever Shala's Phantasm attacks, you may sacrifice a creature. If you do, Shala's Phantasm deals 3 damage to any target.

When Shaman of Burning Ashes enters, return target instant or sorcery card from your graveyard to your hand. When you do, each opponent loses X life, where X is that card's mana value.

When Shambling Gutless enters, target player discards a card.

As long as Shambling Morass is on the battlefield or in your graveyard, it's a land in addition to its other types.
When Shambling Morass dies, you may pay {1}. If you do, you draw a card and you lose 1 life.

When Shambling Retinue dies, create a 2/2 black Zombie creature token.

Menace, lifelink
Whenever a creature enters under an opponent's control, you may have that player lose 1 life.

You may play Shanty Town from your graveyard as long as seven or more cards are in your graveyard.
Shanty Town enters tapped.
{T}: Add {W} or {B}.
Cycling {1}{W}{B} ({1}{W}{B}, Discard this card: Draw a card.)

Look at the top three cards of your library. Put one of them into your hand, one on top of your library, and one on the bottom of your library.
Reprise {1}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

Shapen's Cruelty deals 3 damage to any target.
Acquiesce (If you cast this spell from your hand, exile it as it resolves. When one or more creatures you control deal combat damage to an opponent, you may cast this card from exile without paying its mana cost.)

Create a colorless Equipment artifact token with “Equipped creature gets +1/+1” and equip {1}. You may attach it to a creature you control.
Inscribe {3}{R} ({3}{R}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

When you cast an instant or sorcery spell, you may sacrifice Shard Flower. If you do, copy that spell. You may choose new targets for the copy.