msem-instigator

At the beginning of your upkeep, if six or more cards are in your graveyard, you may transform Scuttling Gnat.

Concord — {1}{G}: Until end of turn, Seadrake Rider gets +2/+3 and must be blocked if able. Activate only during your turn, only once each turn, and only if there are four or more card types among permanents you control.

Seafoam Slasher gets +1/+1 and has deathtouch as long seven or more cards are in your graveyard.
Cycling {2} ({2}, Discard this card: Draw a card.)

Golden age (If you cast an instant or sorcery spell, activated a nonmana ability, and attacked this turn, enter a renaissance for this game.)
Target creature or planeswalker an opponent controls phases out. If you're in a renaissance, exile it instead.

Choose target card in a graveyard other than a basic land card. Search its owner's graveyard, hand, and library for any number of cards with the same name as that card and exile them. Then that player shuffles.
Scry 1.

When Sealed Evil in a Cage enters, exile target creature an opponent controls with mana value 3 or greater until Sealed Evil in a Cage leaves the battlefield.

When Sealed Riftway enters, exile up to one target card from a graveyard.
{2}, {T}, Sacrifice Sealed Riftway: Exile target player's graveyard. Draw a card.

Sear Flesh deals 3 damage to target creature or planeswalker. If you've cast another spell this turn, it deals 5 damage instead.

Searing Blasphemy deals 2 damage to target creature. If that creature is an Angel, Searing Blasphemy deals 5 damage instead.

Target creature gains winnow until end of turn if you attacked this turn. Searing Insult deals 2 damage to that creature. (Damage dealt to it also causes its controller to lose that much life.)

Reverberate {3}{R} (When you cast this spell, copy it if you paid its reverberate cost. You may choose new targets for the copy.)
Searing Pulse deals 2 damage to any target.

Target permanent you control deals 2 damage to any target.
Inscribe {2}{R}{R} ({2}{R}{R}: Exile this card from your hand inscribed on a creature you control. Whenever that creature attacks, its controller may cast a copy of the inscribed card without paying its mana cost. Inscribe only as a sorcery.)

Exile target creature or planeswalker card from a graveyard. Search its controller's hand, graveyard, and library for any number of cards with the same name as that card and exile them. Then that player shuffles.

This spell can't be countered.
Draw a card.
Reprise {2}{U} (As you cast an instant or sorcery spell, you may exile one card with reprise from your graveyard and pay its reprise cost. If you do, add its effects to that spell.)

As Secrets of the Orrery enters, choose fact or fiction.
Foresight — Whenever you draw your second card each turn,
• Fact — Target creature can't be blocked this turn.
• Fiction — You may tap target creature. If you do, put a stun counter on it.

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

When Seductive Seashell enters, target player mills two cards.
{2}, Sacrifice Seductive Seashell: Target player mills four cards.

Look at the top two cards of target player's library. Put one of those cards on the bottom of their library and the rest on top.
Fuse (You may cast one or both halves of this card from your hand.)

Search your library for a basic land card, reveal it, put it into your hand, then shuffle.(Cast a copy of this spell once while this creature is on the battlefield.)

Target creature gets +1/+1 and gains first strike until end of turn.
Fabled {3}{W} (Then if you cast this for its fabled cost, put it onto the battlefield transformed attached to that creature.)

Draw a card.
Whenever Seek Guidance is put into your graveyard from your hand or library, scry 2. (This doesn't include being cast.)

Reveal the top three cards of your library. Put one into your hand and the rest on the bottom of your library in any order.

(Add a quest counter as this enters. Sacrifice after 3.)
Whenever you attack, add a quest counter.
Create a 0/1 white Human creature token named Lost Child.
Scry 2.
Exile a token you control named Lost Child. If you do, create two 1/1 white Soldier creature tokens and you gain 4 life.

Flying
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)

As long as you control four or more lands, Seeker of Untouched Beauty gets +2/+2 and has trample.
When Seeker of Untouched Beauty dies, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.