msem-instigator

{T}: Look at the top two cards of your library, then put them back in any order.

When Stoic Observation enters, mill two cards, then you may return a creature card from your graveyard to your hand.
{3}{G}, Exile a creature card from your graveyard: Create a 2/2 green Wolf creature token. You gain 2 life.

When Stolen Innovations enters, target opponent reveals their hand. You choose an instant or sorcery card from that player's hand or graveyard and exile it.
You may cast each spell you cast from your hand as a copy of the exiled card. You may spend mana as though it were mana of any color to cast spells this way.

When Stolen Light enters, exile target nonland permanent an opponent controls until Stolen Light leaves the battlefield.
{W}{U}{B}{R}{G}: Put a permanent card exiled with Stolen Light onto the battlefield under your control. It's a 3/3 Horror creature in addition to its other types.

{1}, {T}, Sacrifice Stolen Strain: Target creature gains lifelink until end of tun.
{1}, {T}, Sacrifice Stolen Strain: Target creature gains winnow until end of turn. (Damage dealt to it also causes its controller to lose that much life.)

Trample

Reach
Stonebark Incinerator gets +2/+0 and has trample as long as you control a Dwarf.
Stonebark Incinerator gets +0/+2 and has vigilance as long as you control a Elf.

Reach
Whenever this creature attacks, target creature with power less than or equal to the number of creatures you control can't block this turn.
{3}{G}: Attacking creatures get +1/+0 and gain trample until end of turn.

Flying
Tap an artifact you control, a creature you control, and an enchantment you control: Return Stonecut Lammasu from your graveyard to your hand. Activate only as a sorcery.

When Stonefall Golem leaves the battlefield, destroy target permanent.

Whenever Stonehoof Familiar is dealt damage, put a +1/+1 counter on it. (It must survive the damage to get the counter.)
Menagerie — As long as there are five or more creature types among creatures you control, all damage that would be dealt to you or other permanents you control is dealt to Stonehoof Familiar instead.

Improve {1} ({1}: Put a +1/+1 counter on this creature. This costs {1} more to activate for each +1/+1 counter on it. Improve only as a sorcery.)
{3}{W}: Return target nonland permanent card with mana value 1 or less from your graveyard to your hand. This ability cost {1} less to activate for each counter on Stoneport Provisioner.

Whenever you cast a spell, if it isn't your main phase, you may have Stoneshrine Guardian's base power and toughness become 4/1 or 1/4 until end of turn.

Flash (You may cast this spell any time you could cast an instant.)
Enchant creature
Enchanted creature gets +2/+2.

Trample (This creature can deal excess combat damage to the player or planeswalker it's attacking.)
Renown 3 (When this creature deals combat damage to a player, if it isn't renowned, put three +1/+1 counters on it and it becomes renowned.)

Double strike, vigilance, lifelink

Creature spells cost {1} more to cast.
At the beginning of your upkeep, put a decay counter on Stonewood Sanctuary. Then if it has three or more decay counters on it, sacrifice it.

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

At the beginning of your upkeep, if Stonework Infantry is on the battlefield, each player returns all cards named Stonework Infantry from their graveyard to the battlefield.

Haste
Storm Entity enters with a +1/+1 counter on it for each other spell cast this turn.

Whenever a permanent you control becomes tapped, Storm Servant gets +1/+1 until end of turn.

Colossal 3—{4}{R} (You may cast this for its colossal cost to have it enter with three +1/+1 counters; or pay {4}{R} as a sorcery: Put three +1/+1 counters on it if it has none.)
When Storm-Eye Salamander's colossal ability puts one or more counters on it, exile the top three cards of your library. Until the end of your next turn, you may play one of those cards.

Whenever you cast an instant or sorcery spell, you may attach Stormbreaker's Edge to target creature you control.
Equipped creature gets +3/+0.
Equip {3}

Stormbred Elemental gets +1/+1 as long as you control an Island.
{U}: Stormbred Elemental gains flying until end of turn.