msem-instigator

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

{T}: Add {C}.
{T}: Add one mana of any color among planeswalkers you control.
{1}, {T}: Put a loyalty counter on target planeswalker that activated a loyalty ability this turn.

Sparring Ground enters with a +1/+1 counter on it.
{T}: Add {C}.
Whenever a creature you control enters, you may move a +1/+1 counter from Sparring Ground onto that creature.

Spawning Barrens enters tapped unless you have 15 or less life.
{T}: Add {B} or {R}.

Creatures your opponents control can't block alone. (They can block different creatures.)

Spined Spire enters tapped.
{T}: Add {U} or {R}.
{1}{U}{R}: Until end of turn, Spined Spire becomes a Lizard creature with menace in addition to its other types.
Scavenge {1}{U}{R}

Spinerock Canyon enters tapped unless you control a basic land.
{T}: Add {R} or {W}.

Haste
Ward—Sacrifice a creature.
Spinning Gears Abomination enters with X +1/+1 counters on it.
Spinning Gears Abomination can't attack alone.

Spiny Ridge enters tapped. When it does, it explores. (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.)
{T}: Add {R}.
{4}{R}: Spiny Ridge becomes a Lizard creature. (This effect lasts indefinitely.)

({T}: Add {R} or {W}.)
Spiraling Canyon enters tapped unless you control a basic Mountain or a basic Plains.

({T}: Add {R}.)
Spire Sanctuary enters tapped with two sanctum counters on it.
{T}, Remove a sanctum counter from Spire Sanctuary: Add {B} or {G}.

Spired Canopy enters tapped unless another player controls a land that could produce {G} or {U}.
{T}: Add {G} or {U}.

Spires of Caulte enters tapped.
{T}: Add {B} or {R}.
{B}{R}: Until end of turn, Spires of Caulte becomes a 3/2 black and red Construct creature with with menace and “Whenever this creature attacks or blocks, torment yourself.” It's still a land. (To torment yourself, lose 3 life unless you discard a card or sacrifice a nonland permanent.)

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {W} or {U}.

{T}: Add {C}.
{T}: Add one mana of any color among creatures you control.
{X}: Spirit Blossom Shrine becomes an X/X Spirit creature until end of turn. It's still a land. Activate only if you control a creature with power X.

Splendid Scenery enters tapped unless you control a basic land.
{T}: Add {G} or {W}.

{T}: Add {C}.
{4}, {T}: Create a 0/1 white Goat creature token.
{T}, Sacrifice X Goats: Add X mana of any one color. You gain X life.

Each creature you control with power 4 or greater can't be blocked by creature tokens.

({T}: Add {G}, {W}, or {U}.)
Stalwart Dominion enters tapped.

{T}: Add {C}.
{T}, Pay 1 life: Add {G}.
{G}, {T}: Add one mana of any color.

{T}: Add {C}.
{T}, Pay 1 life: Add {B}.
{B}, {T}: Add one mana of any color.

{T}: Add {C}.
{T}, Pay 1 life: Add {W}.
{W}, {T}: Add one mana of any color.

{T}: Add {C}.
{T}, Pay 1 life: Add {U}.
{U}, {T}: Add one mana of any color.

{T}: Add {C}.
{T}, Pay 1 life: Add {R}.
{R}, {T}: Add one mana of any color.

{T}: Add {C}.
{3}, {T}: Aetherize target permanent you control. Activate only as a sorcery. (To aetherize, create a token that's a copy of it, then exile that token.)