msem-instigator

{2}{B}, {T}, Sacrifice Sculler's Oar: Return up to two target creature cards from your graveyard to your hand.

Sculpted Observatory enters tapped.
{T}: Add {W} or {U}.
{1}, {T}: Add one mana of any color.

Seaside Citadel enters tapped.
{T}: Add {G}, {W}, or {U}.

Scry 2, then draw two cards. (Look at the top two cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

{T}, Sacrifice a creature: When you next cast an instant or sorcery spell this turn, copy that spell. You may choose new targets for the copy.

{T}, Sacrifice a creature: Target player discards a card and loses 1 life. Activate only as a sorcery.

Flash
Flying
When Seeker Amalgam enters, you may counter target spell with mana value less than or equal to the number of Elementals you control.

At the beginning of your end step, for each opponent, destroy up to one target creature that player controls with power less than or equal to the amount of life that player lost this turn.
{3}{R}: Selezzar, Tyrant of Endak deals 2 damage to each opponent.

Equipped creature gets +1/+1 and has deathtouch.
{1}: Serpent Staff becomes a 1/1 green Snake creature with deathtouch and loses all other abilities until end of turn.
Equip {3}

Encourage ({T}: Another target creature you control gets +1/+1 until end of turn. Encourage only as a sorcery.)
Whenever Serul Cove Escort encourages a creature, that creature gains flying until end of turn.

Enchant creature
Enchanted creature can't attack.
Civilized — Enchanted creature can't block and its activated abilities can't be activated if you control an artifact, a creature, and an enchantment.

[+1]: Up to two target creatures you control each get +1/+0 and gain first strike until end of turn.
[0]: You may sacrifice a creature. If you do, Shala Na, Urshadi Apostate deals 3 damage to any target.
[–3]: Discard your hand, then draw three cards.

Lifelink
Each other artifact creature you control enters with an additional +1/+1 counter on it.

Flash
Flying
When Sharuum, Archmagocrat enters, return to the battlefield all nonlegendary artifact cards in your graveyard that were put there from the battlefield this turn.

Assault {2}{R}{G} (Whenever this attacks, if it has no +1/+1 counters on it, you may pay its assault cost to put a +1/+1 counter on it.)
When Shemesh assaults, other creatures you control get +2/+2 and gain trample until end of turn.

Whenever a land you control enters, you may tap target creature.

Return target creature card from your graveyard to the battlefield. Put a +1/+1 counter on it for each of its colors.

Shock deals 2 damage to any target.

First strike
Whenever Sighted-Caste Knight deals combat damage to a player, draw a card.

Untap target creature. It gets +2/+2 until end of turn.
Cycling {W} ({W}, Discard this card: Draw a card.)

Creature tokens you control get +1/+0.

Equipped creature has “{T}: Reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand.”
Equip {2}

Flying
Sire of Empires gets +1/+1 as long as you control another creature, has lifelink as long as you control an enchantment, and has vigilance as long as you control an artifact.

Reach

Flying
Cycling {U} ({U}, Discard this card: Draw a card.)