msem-instigator

This spell costs {1} less to cast for each other spell you've cast this turn.

Flying
Whenever Spellgorger Elemental attacks, discard a card at random. If an instant or sorcery card is discarded this way, Spellgorger Elemental deals 3 damage to any target. Otherwise, draw a card.

Whenever you cast your second spell each turn, if it's an instant or sorcery spell, you may pay {1}{R}. If you do, gain control of target creature an opponent controls until end of turn. Untap that creature. It gains haste until end of turn.

Spellwoven Monster can't be the target of spells or abilities in any zone.
As you cast an instant or sorcery spell, reveal cards from the bottom of your library until you reveal an instant or sorcery card. You may add that card's effects to that spell. Then shuffle.

Flying
When Sphinx of Riddles enters, secretly choose a card name. You may reveal the chosen name any time.
Whenever a spell an opponent controls with the chosen name resolves, you may draw two cards.

Untap target creature. It gets +2/+4 and gains reach until end of turn.

Once each turn, when one or more cards are put into an opponent's graveyard from their library, you may draw a card.

Reach
Spined Tarantula gets +1/+1 for each creature with flying your opponents control.

When Spinegraft Disabler enters, exile target creature until Spinegraft Disabler leaves the battlefield.

({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}.

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.

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.

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.

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.