Prowess
When Satyr Arsonist enters, destroy up to one target nonbasic land. Its controller may search their library for a basic land card, put it onto the battlefield tapped, then shuffle.

Hexproof from permanents

Whenever you cast an instant or sorcery spell, choose one that hasn't been chosen this turn —
• Create a 1/1 colorless Construct artifact creature token.
• Discard a card, then draw a card.
• Add one mana of any type.

{1}{R}, {T}, Discard a card: Draw a card. Scalding Crucible deals 1 damage to each opponent.
Spellcharge 5

Players can't gain life.
Whenever a player casts a spell, Scathing Remarks deals 1 damage to that player for each of that spell's colors.

When Scattering Swine deals combat damage to a player, you may return a permanent you control to its owner's hand. If you do, that player loses 3 life unless they discard a card that shares a type with the returned permanent.

{3}, {T}, Sacrifice Scorching Illuminator: Return target instant or sorcery card from your graveyard to your hand. Add one mana of any color.

Trample
When Scourge of Capitalism enters, it fights target creature with the greatest power or tied for the greatest power among creatures you don't control. Excess damage is dealt to that creature's controller instead.

Haste
Solidarity

Enchant creature
Enchanted creature gets -1/-1.
Sacrifice an artifact: Destroy enchanted creature. Activate only as a sorcery.

Whenever one or more creatures you control deal combat damage to a player, you may draw that many cards. If you do, discard a card.
Exile two creature cards from your graveyard: Scrapyard Mecha becomes an artifact creature until end of turn. Activate only as a sorcery.
Crew 2

Flying
Creatures you control with base power 1 or less get +1/+0.

When Scruffy Rascal enters, mill three cards. You may put a permanent card from among the cards milled this way into your hand. If you don't, create a Treasure token.

Scuttle Tank enters with a defender counter on it.

Surface {U}. Scuttling Cicada surfaces transformed.

When Sea Breeze enters, return up to one target creature to its owner's hand, then surveil 1.

When Seafloor Scavenger enters or deals combat damage to a player, you may return target exiled card with surface you own to your hand.

Flash
When Seal Away enters, exile target tapped creature an opponent controls until Seal Away leaves the battlefield.

At the beginning of each end step, create a 2/2 white and blue Seal Orb creature token if you activated two or more nonmana abilities this turn.
{W}{U}: Scry 1. You gain 1 life.

Vigilance
When Seasoned Spymaster enters, teach target creature vigilance.

Lifelink
Whenever Secluded Gorgon dies, you may bless target creature.

Secluded Hangar enters tapped unless you control a basic non-Forest land.
{T}: Add {G}.
{2}, {T}: Put a +1/+1 counter on target creature that entered this turn.

Flash
When Security Initiative enters, you may tap or untap target nonland permanent. Then draw a card.
An opponent controls three or more tapped nonland permanents.

Flying
Whenever Seeker Orbs becomes tapped, scry 1.

Whenever a basic land you control enters, put a +1/+1 counter on Seeker of New Horizons. If you control seven or more lands, bless that land.