msem-instigator

When Scaleshredder enters the battlefield, you may have it consume. If you do, reveal cards from the top of your library until you reveal a creature card. Put that card onto the battlefield and the rest on the bottom of your library in a random order. (To consume, sacrifice another creature or exile a creature card from your graveyard.)

Put target creature on top of its owner's library. All other creatures that player controls get -2/-2 until end of turn.

Flying
When Scorchpass Sovereign enters the battlefield, it deals 1 damage to each creature with flying you don't control.

Embellish {3}{B} (If you cast this spell for {3}{B}, create a 1/1 blue Thopter artifact creature token with flying when it enters the battlefield.)
When Scrap Spiral enters the battlefield, target creature gets -2/-2 until end of turn.
{3}{B}, {T}, Sacrifice an artifact: Target creature gets -2/-2 until end of turn.

When Scrying Pool enters the battlefield, scry 2.
{1}, {T}: Add one mana of any color.

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

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

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

{T}, Sacrifice a creature: When you cast your next 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 2 life. Activate only as a sorcery.

Mill four cards, then return a creature or enchantment card from your graveyard to you hand. You gain 3 life.

Serpentine Woods enters the battlefield tapped.
{T}: Add {B} or {G}.
{2}{B}{G}, {T}, Sacrifice Serpentine Woods: Draw a card.

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.

Chronicle (As this enters and after your draw step, add a lore counter. Stop after III.) [4/4]
[Lore I-II] Mill two cards.
[Lore III] Return target creature card from your graveyard to your hand.

Equipped creature gets +2/+2 and has ward {2} and “Whenever this creature attacks, draw a card, then you may put a land card from your hand onto the battlefield.”
Equip {2}

Heroic — Whenever you cast a spell that targets Setessan Avenger, create a 1/1 green Nymph Dryad enchantment creature token with “{T}: Add {G}.”
Whenever Setessan Avenger deals combat damage to a player, untap all lands and Dryads you control.

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

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

Sheltered Haven enters the battlefield tapped.
{T}: Add {G} or {W}.
{2}{G}{W}, {T}, Sacrifice Sheltered Haven: Draw a card.

Whenever you scry, put a +1/+1 counter on Shimmershell.

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

Flying, vigilance

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.