msem-instigator

Shoupan Shrine enters the battlefield tapped.
{T}: Add {B} or {R}.
{B/R}, {T}, Sacrifice Shoupan Shrine: Put a +1/+1 counter on target creature you control. Activate only as a sorcery.

Whenever you create an Idol token, put a +1/+1 counter on Shrine of Elder Lords.
{T}: Add {C}.
{3}: Put a +1/+1 counter on Shrine of Elder Lords, then you may have it become a 0/0 Elemental creature with vigilance until end of turn. It's still a land.

{T}: Add {C}.
{T}: Add one mana of any color. Activate only if you've cast a noncreature spell this turn.

{T}: Add {C}.
Shrine of the World-Shepherd's power and toughness are each equal to the number of differently named lands you control.
{3}{G}: Shrine of the World-Shepherd becomes a Beast creature in addition to its other types until end of turn.

{T}: Add {C}.
{T}: Choose a color. Add one mana of that color unless you control a permanent of that color. Spend this mana only to cast a permanent spell.

{2}{U}: Target creature can't be blocked this turn.

Frozen Hinterlands enters the battlefield tapped.
{T}: Add {W} or {B}.
{1}{W}{U}: Until end of turn, Frozen Hinterlands becomes a 3/3 white and black Illusion creature with with lifelink 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}, Pay 1 life: Add one mana of any color. Spend this mana only to cast an instant or sorcery spell.

({T}: Add {B} or {G}.)
Shuddering Node enters the battlefield tapped.
{1}, {T}: Add {B}{B} or {G}{G}.

Vigilance
Whenever Sibling of All Elements attacks, it gains flying until end of turn if you control a creature with flying. The same is true for first strike, double strike, deathtouch, indestructible, lifelink, menace, and trample.

Prevent all combat damage that would be dealt to Silent Reaver.
Prevent all combat damage Silent Reaver would deal to creatures.

Silent Ridge enters the battlefield tapped.
{T}: Add {B}.
Desertcycling {1}{B} ({1}{B}, Discard this card: Search your library for a Desert card, reveal it, and put it into your hand, then shuffle.)

{T}, Pay 1 life: Add {G}.
{8}{G}, Exile Singers' Grove from your hand: Creatures you control get +7/+7 until end of turn.

{T}, Sacrifice Skeletal Oasis: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Sky-High Spires enters the battlefield tapped unless you have two or more opponents.
{T}: Add {W} or {U}.

Skylight Fortress enters the battlefield tapped.
When Skylight Fortress enters the battlefield, you may search your library for a card named Skylight Fortress, reveal it, put it into your hand, then shuffle.
{T}: Add {C}.

At the beginning of combat on your turn, target creature you control with flying gets +1/+1 until end of turn.

Slipsand Oasis enters the battlefield tapped unless you played it from exile.
{T}: Add {W} or {B}.

Slipstream Horizon enters the battlefield tapped.
{T}: Add {U} or {R}.
{U}{R}, {T}, Sacrifice Slipstream Horizon: Conjure a card named Data-Point into your hand. (It's a sorcery that costs {2} with “Draw a card.”)

(Transform this if it's not attached to a creature. Pay {2}{W} as a sorcery to unattach it.)
Enchant creature you control
Slopestrider's Chariot's rider gets +1/+1 and has double strike.

{T}: Add {C}.
{4}, {T}, Sacrifice Slyten Crystal Motherlode: Add {W}{U}{B}{R}{G}.

{T}: Add {C}.
{T}: Add one mana of any color. You can't spend this to cast spells from your hand.

Snow Drift enters the battlefield 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 {U}.
{4}{U}: Snow Drift becomes an Elemental creature. (This effect lasts indefinitely.)