msem-instigator

Equipped creature gets +1/+2 and has vigilance.
Equip {3}

When Sheltered Diviner enters the battlefield, each player mills three cards.

Whenever a creature you control dies, create an Idol token. (It's an artifact with “{1}, Sacrifice this artifact: Put a +1/+1 counter on target creature. Activate only as a sorcery.”)
Whenever you sacrifice a noncreature permanent, each opponent loses 1 life and you gain 1 life.

Flash
This spell can't be countered.
Whenever Shigurei attacks, you may activate an ability of a creature you control without paying its cost.
{1}{G}{U}: Target permanent becomes a colorless Island land until end of turn.

Trample
When Shigurei, the Floodbringer enters the battlefield, up to three target permanents become colorless Island lands.

Shimmering Seadragon gets +1/+0 and can't be blocked as long as you control a legendary creature.

Create a token that's a copy of target creature.
Metamorph {2}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up and cast it at any time for its metamorph cost.)

Enchant creature you control
At the beginning of your upkeep, create a token that's a copy of enchanted creature.

{8}{U}{U}: Monstrosity 5. (If this creature isn't monstrous, put five +1/+1 counters on it and it becomes monstrous.)
When Shipway Whale becomes monstrous, target player exiles all cards in their library, then shuffles their graveyard into their library.

This spell has flash as long as an opponent is cursed.
Return target creature to its owner's hand.
Draw a card.

Flying
When Shoal Raker enters the battlefield, draw a card if an opponent is cursed.

Shock Blast deals X damage to target creature, where X is the number of instant and sorcery cards in your graveyard.

When Shojiro, the Wavewaker enters the battlefield, submerge up to eight target creatures your opponents control. (To submerge a card, exile it, then put it on the battlefield face down under its owner's control as a 2/2 creature.)

{3}{U}{U}: Monstrosity 4. (If this creature isn't monstrous, put four +1/+1 counters on it and it becomes monstrous.)
When Shorecrash Octopus becomes monstrous, return target instant or sorcery card from your graveyard to your hand.

Equipped creature gets +1/+1.
Equip {1}

{2/W}{2/W}: Shrapnel Golem deals 3 damage to target creature blocking it.

Choose one —
• Shredding Blizzard deals 5 damage to target creature.
• Up to three target creatures can't block this turn.

Flying
Revive {5}{U} ({5}{U}, Exile this card from your graveyard: Create a token that's a copy of it except it has no mana cost. Revive only as a sorcery.)

Shrewd Sikoyo can't be blocked by creatures with power 4 or greater.
Shrewd Sikoyo gets +1/+0 as long as you have at least two more cards in hand than any opponent.

Lifelink
Whenever an Aura becomes attached to Shrieking Gnoll, put a +1/+1 counter on Shrieking Gnoll, then target creature an opponent controls gets -1/-1 until end of turn for each +1/+1 counter on Shrieking Gnoll.

Flying
Sacrifice a creature: Shrieking Nightwing gets +1/+1 until end of turn.

Flying
Resolute — At the beginning of combat on your turn, Shrill Griffin gains vigilance until end of turn if its power is greater than its base power.

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.

Enchant creature
When Shrouded Spoils enters the battlefield, draw two cards.
Enchanted creature can't be blocked.

Draw a card. If this is the third spell you've cast this turn, create a 2/2 blue Drake creature token with flying. If this is the sixth spell you've cast this turn, exile it, then return up to three target instant and/or sorcery cards from your graveyard to your hand and untap up to six lands.