msem-instigator

Whenever Solemn Stag perseveres, put two +1/+1 counters on it. (A creature perseveres when it survives damage.)

{T}: Add {C}.
Satrapies you control have “{1}{W}, {T}, Exile a card from your graveyard: Create a 1/1 white Soldier creature token.”

As Soli Fortress enters, you may pay 1 life. If you don't, Soli Fortress enters tapped.
Satrapies you control have “{T}: Add {W}.”

(As an Encounter enters, choose an opponent to protect it. You and others can attack it. When defense counters are removed, create a 0/0 Army token if you don't control one, then put that many +1/+1 counters on a Army you control.)
When Soli Rising enters, 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.

Soli Sanctuary enters tapped.
Satrapies you control have “{T}: Add {W} or {U}.”

Soli Temple enters tapped.
Satrapies you control have “{T}: Add {G} or {W}.”

Tap all lands target player controls and that player loses all unspent mana.

Whenever Solvent Tide attacks, create a Vial token. (It's an artifact with “{1}, Sacrifice this and another permanent: Draw a card. Activate only during your turn.”)

({T}: Add {B} or {G}.)
Somber Marsh enters tapped.

Somber Meadow enters tapped.
{T}: Add {W} or {B}.
{1}, {T}: Add one mana of any color.

You may look at the top card of your library any time.
You may play lands from your graveyard and the top of your library.

When Something in the Woods enters or at the beginning of your upkeep, Something in the Woods explores. If it explores a creature card, you may have it become a copy of that card. (It loses this ability. To explore, reveal the top card of your library. Put that card into your hand if it's a land. Otherwise, put a +1/+1 counter on this, then you may put that card into your graveyard.)

Creatures you control get +2/+2 and gain trample until end of turn.

Put three +1/+1 counters on target creature you control. It voyages. (If it isn't blocking or targeted by another spell or ability, it phases out.)

Alpha (You may have this creature enter with a +1/+1 counter on it. If you do, it becomes alpha and can only attack alone.)
Whenever a creature you control attacks alone, untap all lands you control.

Defender, reach
When Soothevine Elemental enters, draw a card.

Equipped creature gets +1/+0 for each instant and sorcery card in your graveyard.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

As Sorcerous Spyglass enters, look at an opponent's hand, then choose any card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Reach
{3}, Exile Sorrowful Seeker from your hand: Draw a card. You may cast this card for as long as it remains exiled.

When Sorrowslayer enters, put a +1/+1 counter on target creature.
Remove a +1/+1 counter from Sorrowslayer: Trigger a death knell of a permanent you control. Activate only once each turn and only as a sorcery.

Whenever equipped creature attacks or blocks, you gain 2 life.
Equip {3} ({3}: Attach to target creature you control. Equip only as a sorcery.)

Choose one—
• Soul Flame deals X damage to target nonred creature.
• Target red creature gets +X/+0 until end of turn.

{1}, {T}: Exile target card from a graveyard. Scry 1.
{T}, Exile Soul Gate: Exile all graveyards.

Protection from colored spells
{5}{C}{C}: Exile target colored permanent.
{5}{C}{C}, Exile Soul of Muetar from your graveyard: Exile target colored permanent.

Tap two untapped creatures you control: Harmonize. (Trigger up to one harmony of one permanent you control.)
Harmony — Choose one —
• Soul of New Alores becomes a creature in addition to its other types until end of turn.
• Put two +1/+1 counters on target permanent.