mtg.wtf

Defender
{B}: Slithering Shade gets +1/+1 until end of turn.
Hellbent — Slithering Shade can attack as though it didn't have defender as long as you have no cards in hand.

Swampwalk
When Slithery Stalker enters the battlefield, exile target green or white creature an opponent controls.
When Slithery Stalker leaves the battlefield, return the exiled card to the battlefield under its owner's control.

{1}, {T}, Discard a card: Create a 1/1 colorless Sliver artifact creature token named Metallic Sliver.

Whenever another artifact enters the battlefield under your control or another artifact you control leaves the battlefield, you may pay {1}. If you do, target player loses 1 life and you gain 1 life.

When Slum Reaper enters the battlefield, each player sacrifices a creature.

Slurrk, All-Ingesting enters the battlefield with five +1/+1 counters on it.
Whenever Slurrk or another creature you control dies, if it had a +1/+1 counter on it, put a +1/+1 counter on each creature you control that has a +1/+1 counter on it.
Partner

Improvise
Whenever a nontoken artifact you control is put into a graveyard from the battlefield, create a 1/1 colorless Servo artifact creature token.

Whenever Sly Spy deals combat damage to a player, that player reveals their hand. You choose a card from it with the longest name. That player discards that card.

Whenever Sly Spy deals combat damage to a player, you may destroy target creature facing left in its art. (Creatures without faces don't face anywhere.)

Whenever Sly Spy deals combat damage to a player, that player loses a finger until Sly Spy leaves the battlefield. (The finger is chosen by its owner and can't roll dice or touch cards.)

Whenever Sly Spy deals combat damage to a player, you may destroy target creature facing right in its art. (Creatures without faces don't face anywhere.)

Whenever Sly Spy deals combat damage to a player, that player reveals the top card of their library. Put that card into your hand and you lose life equal to its mana value.

Whenever Sly Spy deals combat damage to a player, roll a six-sided die. That player loses life equal to the result.

Each player loses 1 life, discards a card, sacrifices a creature, then sacrifices a land.

{2}{R}, Sacrifice Smelt-Ward Ignus: Gain control of target creature with power 3 or less until end of turn. Untap that creature. It gains haste until end of turn. Activate only as a sorcery.

Whenever you cast an instant or sorcery spell, target creature an opponent controls can't block this turn.

Smiting Helix deals 3 damage to any target and you gain 3 life.
Flashback {R}{W}

Flying
Creatures with flying your opponents control get -1/-1.

Whenever Smogsteed Rider attacks, each other attacking creature gains fear until end of turn.

At the beginning of your upkeep, target player loses 1 life.
Sacrifice Smoldering Tar: It deals 4 damage to target creature. Activate only as a sorcery.

When Smoldering Werewolf enters the battlefield, it deals 1 damage to each of up to two target creatures.
{4}{R}{R}: Transform Smoldering Werewolf.

Draft Smuggler Captain face up.
As you draft a card, you may reveal it, note its name, then turn Smuggler Captain face down.
When Smuggler Captain enters the battlefield, you may search your library for a card with a name you noted for cards named Smuggler Captain, reveal it, put it into your hand, then shuffle.

You may discard a Forest card rather than pay this spell's mana cost.
Prevent all combat damage that would be dealt by unblocked creatures this turn.

Enchant creature
Enchanted creature has poisonous 3.

Whenever an opponent casts a blue or black spell, you may create a 1/1 green Snake creature token.