msem-instigator

Up to three target creatures each get +1/+1 until end of turn.

Schoolmaster gets +1/+1 for each other Merfolk you control.
When Schoolmaster enters, create a 1/1 white Merfolk creature token.

Target creature you control gets +1/+2 until end of turn. If that creature is white, create a white Aura enchantment token with enchant creature and “Enchanted creature has first strike” attached to that creature.

Add three mana of any one color.

When Scintillating Tome enters, choose a nonbasic card name.
{T}: Scry 1, then you may reveal the top card of your library. If a card with the chosen name is revealed this way, put it into your hand.

Scion of Belmord has lifelink as long as it's embattled. (A creature is embattled if it has a counter on it or a permanent you control attached to it.)

When this creature enters, you may put a -1/-1 counter on a creature you control. If you do, look at the top five cards of your library. You may reveal a land card from among them and put it into your hand. Put the rest into your graveyard.

Disgraced 1 (This enters with a -1/-1 counter. Whenever it deals combat damage to a player, remove all -1/-1 counters from it.)
Whenever you put one or more -1/-1 counters on Scion of Fiends or another creature, Scion of Fiends deals that much damage to each opponent.

When Scion of Pestilence enters, create a black enchantment token named Blight with “At the beginning of your upkeep, you lose 1 life.”

Flying
Civilized — Scion of Sannuria has vigilance as long as you control an artifact, a creature, and an enchantment.

When Scion of Sarrithaz enters, create a 2/2 black Zombie creature token.
{2}{B}, Sacrifice a creature: Draw a card.

Vigilance
Other Knights and Soldiers you control get +1/+1.
{2}{B}, {T}, Sacrifice a Knight or Soldier: Destroy target creature or planeswalker. Activate only as a sorcery.

Scion of the Wild's power and toughness are each equal to the number of creatures you control.

When this enchantment enters, exile target creature until this enchantment leaves the battlefield.
Foretell {1}{W} (During your turn, you may pay {2} and exile this card from your hand face down. Cast it on a later turn for its foretell cost.)

Sacrifice Scions of Old Jidai: Target player gains life equal to the life that player has lost this turn.

This spell costs {2} less to cast if its target has the same name as a card in a graveyard.
Scoff deals 3 damage to any target.

Draw two cards.
Flashback—{2}{U}, Discard a card. (You may cast this card from your graveyard for its flashback cost. Then exile it.)

Scorch deals 3 damage to any target.

Enchant creature
Enchanted creature gets +2/-2.

Scorching Dragonfire deals 3 damage to target creature or planeswalker. If that permanent would die this turn, exile it instead.

Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
Scorchland Vandal attacks each combat if able.

Wither (This deals damage to creatures in the form of -1/-1 counters.)
Whenever a creature with wither deals combat damage to an opponent, Scorchmark Seer deals 2 damage to that player.

Flying
When Scorchpass Sovereign enters, it deals 1 damage to each creature with flying you don't control.

Counter target spell with no subtypes. Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)

Whenever you cast a spell, Scorned Figurant gets +1/+1 until end of turn.