Sillaman District enters tapped unless you control a Forest, a Plains, and an Island.
{T}: Add {G}, {W}, or {U}.

When Sillaman Regrafter enters, put a +1/+1 counter on target creature you control.
Whenever a creature you control dies, you may move a counter from it onto another target creature.

Sleeper Insurgent doesn't untap during your untap step.
Whenever Sleeper Insurgent becomes the target of a spell or ability you control, untap it. This ability triggers only once each turn.

Flash
Flying
When Sleeper Strix enters, tap up to one target creature.
You may look at an additional card each time you surveil.

Return target creature to its owner's hand. If you controlled it, create a token that's a copy of it. Otherwise, create a 0/0 colorless Robot artifact creature token with a +1/+1 counter on it.

When Sola enters, create a Treasure token.
{2}, Sacrifice a Treasure: You gain 3 life.
{2}, Sacrifice a Treasure: Draw a card.

When Sparks of a Revolution enters, create a 1/1 colorless Soldier creature token. It gains haste until end of turn.
Three or more sources you controlled dealt damage this turn.
A source you controlled dealt 3 or more damage this turn.

Whenever another creature you control enters, you may pay {X}{X}. If you do, put X +1/+1 counters on that creature.
{T}: Add one mana of any color.

Splintering Blast deals 4 damage to target creature. If you controlled a creature with menace as you cast this spell, instead Splintering Blast deals 4 damage divided as you choose among up to two target creatures.

Enchant creature
When Stasis Chamber enters, if you control a creature with vigilance, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Sterling enters under the control of an opponent of your choice.
At the beginning of your upkeep, surveil 1.
Play with the top card of your library revealed.
Your opponents may play lands and cast spells from the top of your library during their turns, and they may spend mana of any type to cast spells this way.

Any number of creatures you control fight different creatures you don't control. Each other creature you control gets +3/+3 and gains trample until end of turn.

{T}: Create a Treasure token.
{T}, Sacrifice a Treasure: Put a +1/+1 counter on target creature. Activate only as a sorcery.
{T}, Sacrifice two Treasures: Create a 0/0 colorless Robot artifact creature token with four +1/+1 counters on it. Activate only as a sorcery.
{3}: Untap Subsidized Market.

You may cast spells as though they had flash.
Whenever you cast a spell, you may tap or untap target nonland permanent.

When Survivors of the New World enters, if it isn't a token, create two tokens that are copies of it.
When Survivors of the New World dies, reveal cards from the top of your library until you reveal a creature card. Put that card into your hand and the rest on the bottom of your library in a random order.

When Sustainable Investments enters, create a Treasure token.
Treasures you control have “{T}: Add one mana of any color.”

Test Subject Alpha enters with a +1/+1 counter and a trample counter on it.
At the beginning of your upkeep, you may move a counter from Test Subject Alpha onto another creature.

If you would draw a card while your library has no cards in it, instead you may put a card you own from outside the game into your hand.
{T}: Draw two cards, then discard a card.

When The First Battalion enters, create two 2/2 colorless Minion creature tokens with decayed.
Minions you control lose all abilities.

Equipped creature gets +2/+2.
As long as there are five colors among permanents you control, equipped creature has indestructible.
Equip {5}. This ability costs {1} less to activate for each of its target's colors.

When The Quindral Accords enters, make a pledge.
Pledge — {3}{W}{U}{B}{R}{G}: Create a 5/5 Robot artifact creature token named Sentry of the New World that's all colors, then look at the top five cards of your library. Put one of them into your hand and the rest into your graveyard. Activate only as a sorcery unless you're making a pledge.

Decayed
You may cast The Venerable Veteran from your graveyard.

Draw a card if a creature you control has flying. Do the same for first strike, double strike, deathtouch, haste, hexproof, indestructible, lifelink, menace, reach, trample, and vigilance.

Choose up to one for each color among white, blue, and black among permanents you control.
• Return target artifact or enchantment card from your graveyard to your hand.
• Return target instant or sorcery card from your graveyard to your hand.
• Return target creature or planeswalker card from your graveyard to your hand.
Exile Tiril Agenda.