msem-instigator

Whenever a creature you control becomes the target of a spell, that creature gets +3/+3 until end of turn.

Surging Lightning deals 2 damage to target creature or planeswalker. If you've cast another spell this turn, it deals 4 damage instead.

Submerge up to two target attacking nontoken creatures an opponent controls. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

You may have Surging Wurm assign its combat damage as though it weren't blocked.
Surging Wurm gets +2/+2 as long as seven or more cards are in your graveyard.

Target creature gains double strike and trample until end of turn. (Then exile this card. You may cast the creature later from exile.)

Flash
When Surreal Bakhtak enters, choose one —
• Destroy target tapped creature.
• Tap up to three target creatures.

Flying, prowess
Whenever Surveyor of Skies attacks, you may return a permanent you control to its owner's hand.

Wanderlust — When you cast this spell, you may copy it if you control four or more differently named lands. You may choose new targets for the copy.
Untap target creature you control. It gets +1/+1 and gains hexproof and indestructible until end of turn.

As an additional cost to cast this spell, discard a card.
Return up to one target instant card and up to one target sorcery card from your graveyard to your hand. Exile Sustaining Meditation.

Each other Rogue creature you control enters with an additional +1/+1 counter on it.
Remove a +1/+1 counter from a creature you control: That creature can't be blocked this turn.

Swarm of Sporemites gets +1/+1 for each creature card and Revelation card in your graveyard.

Target creature deals damage equal to its power to its controller.

{T}: Add {C}.
{T}, Pay 1 life: Add {W}.
{5}{W}, {T}, Sacrifice Swaying Sands: Create three 1/1 white Bird creature tokens with flying. Activate only as a sorcery.

Haste
At the beginning of combat on your turn, target creature or Vehicle you control gets +2/+0 until end of turn.

Flash
When Swift Savior enters, if you control a legendary creature, you may have Swift Savior deal 2 damage to target attacking or blocking creature.

Whenever Swiftspear Ambusher and exactly one other creature attack, put a +1/+1 counter on target attacking creature.

Target player reveals their hand. Exile a nonland card from it and put a secret counter on it. As long as that card remains exiled, that player may pay {2} any time they could cast a sorcery to put it into their hand.
{X}{B}{B}, Exile Swipe Secrets from your graveyard: Until end of turn, you may cast target card you exiled with a secret counter on it and mana value X without paying its mana cost.

Sword deals 2 damage to any target.
Fuse (You may cast one or both halves of this card from your hand.)

{5}, {T}, Tap an untapped creature you control: Put target card from your or a teammate's graveyard on top of its owner's library.

At the beginning of your upkeep, you may sacrifice Sylph Spawning. If you do, create three 1/1 blue Nymph creature tokens with flying.

Search your library for a land card, reveal it, put it into your hand, then shuffle.

Counter target spell unless its controller pays {X}. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Syurrai Traitor gets +1/+1 as long as you control a Plains.
{3}{W}: Create a 1/1 white Soldier creature token.

When Syzygy Navigator enters, exile target nonland card from an opponent's graveyard. Copy it. You may cast the copy. (You still pay its costs, including color. Copies of permanents enter as tokens.)
Whenever you cast a spell from anywhere other than your hand, draw a card, then discard a card.

During each of your turns, you may cast a copy of a card in an opponent's graveyard by exiling that card in addition to its other costs. (Copies of permanents enter as tokens.)