msem-instigator

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

({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}.

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

When Spiritual Colpah dies, you may return target creature card from your graveyard to your hand.

Spitfire deals 2 damage to target creature. Up to one target creature you control gets +2/+0 until end of turn.

Shimmer (Whenever this creature attacks, create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the end step.)

Flying, haste
Erratic (When this creature dies, reveal the top four cards of your library. Put a creature card that costs less than this revealed this way onto the battlefield and the rest on the bottom of your library in any order.)
When Splitflame Phoenix dies, you may pay {R}. If you do, return it to its owner's hand.

Vigilance, reach
{T}: Splitshaft Deadeye deals damage equal to its power to target creature with flying.

Flying
Shimmer (Whenever this creature attacks, create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the end step.)

Whenever a land you control enters, you may pay {1}. If you do, create a 1/1 green Saproling creature token.

As an additional cost to cast this spell, sacrifice a permanent.
Sporesowed Disease deals 3 damage to any target and you gain 3 life.

Trample (This creature can deal excess combat damage to defending player or planeswalker while attacking.)
Sprareos Yearling gets +4/+4 as long as you control five or more lands.

Enchant creature
When Sprawled Arming enters, put a +1/+1 counter on enchanted creature.
Enchanted creature has first strike.
{5}: Return Sprawled Arming to its owner's hand.

Target creature gets -2/-2 until end of turn. When that creature dies this turn, create a tapped 2/2 black Zombie creature token.

When Spreading Dissent enters, exile all creatures until Spreading Dissent leaves the battlefield.
{X}: Put a random creature card with mana value X exiled with Spreading Dissent onto the battlefield. Any player may activate this ability.

Distorted (This creature can be blocked by tapped creatures but not untapped creatures.)
Shimmer (Whenever this creature attacks, create a tapped and attacking token that's a copy of it. Exile the token at the beginning of the end step.)

{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.

Whenever a creature you control enters, if you didn't cast it from your hand, put a +1/+1 counter on it.
{3}{W}: Exile target creature you control, then return it to the battlefield under its owner's control.

Target creature gains haste until end of turn. That creature attacks or blocks this turn if able.

Equipped creature has “You may choose not to untap this creature during your untap step” and “{T}: Gain control of target creature with power 5 or greater for as long as you control this creature and it remains tapped.”
Equip {3}

Destroy target attacking creature with mana value 3 or less.

Whenever a creature enters under your team's control, reveal the top card of your library. If it's a creature card, you gain 2 life.

Flash (You may cast this spell any time you could cast an instant.)
When Stampede Instigator enters, target creature gets +2/+3 until end of turn.