msem-instigator

Until end of turn, creatures target player controls lose all abilities and have base power and toughness 0/2.
Inscribe {4}{B}{B} ({4}{B}{B}: 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.)

You may pay {1}{R}{R} and tap an untapped Knight you control rather than pay this spell's mana cost.
Target untapped creature you don't control blocks this turn if able. Other creatures can't block this turn.

Mill five cards, then for each of those cards, a creature you control salvages that card unless an opponent pays 3 life. (Exile it from your graveyard until that creature leaves the battlefield. Whenever that creature deals combat damage to a player, put a card it salvaged into your hand.)

Whenever you cast an instant or sorcery spell, you may attach Stormbreaker's Edge to target creature you control.
Equipped creature gets +3/+0.
Equip {3}

When you cast this spell from your hand, return it to your hand.
Choose one —
• Stormcalling deals 4 damage to any target.
• Exile target artifact.

Whenever equipped creature attacks, it deals damage to defending player equal to the number of instant and sorcery cards in your graveyard.
Equip {2}

Whenever one or more creatures you control attack, you may put a progress counter on Stormcannon Testing.
[PROGRESS 2-3] {T}: Target creature gets +2/+0 until end of turn.
[PROGRESS 4+] {T}: Target creature gets +2/+0 and gains double strike until end of turn.

{T}: Add {C}.
{T}, Exile two cards from your graveyard: Add {U} or {R}.

Stormcharged Pyre enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.

Stormsurge deals 3 damage to any target.
Orchestrate {R} (You may exile this card from your hand anytime you could cast a sorcery for its orchestrate cost. When you next resolve a spell, you may cast this from exile without paying its mana cost.)

Draw a card. Then you may cast an instant spell with mana value 2 or less from your hand without paying its mana cost.

If you would lose the game, instead sacrifice a storied permanent. If you do and your life total is less than 1, it becomes 1.

At the beginning of your upkeep, mill two cards.
{1}{G}, Sacrifice Strange Discovery: Return target card from your graveyard to your hand.

Strange Harbor enters tapped unless you have 15 or less life.
{T}: Add {U} or {R}.

Search your library for two basic land cards and put them onto the battlefield tapped. Then they become 0/1 green Plant creatures with “This creature can't block” in addition to their other colors, types, and abilities.

Enchant opponent
At the beginning of enchanted player's upkeep, they mill two cards.
{U}, Sacrifice Strange Tides: Shuffle up to four target cards from your graveyard into your library.

Target creature gets -3/-3 until end of turn.

Target creature gets -2/-2 until end of turn. If you control two or more Deserts, destroy that creature instead.

Look at the top three cards of your library. Put one of them into your hand and the rest into your graveyard.

Target creature gets +2/+2 until end of turn. Untap it.

Stratospheric Bombardment deals X damage to any target and you gain that much life.

Each player chooses one card in their hand, then discards the rest.

Target player gains X life.

Return target creature to its owner's hand.
Draw a card.

Creatures your opponents control get -3/-0 until end of turn.
Draw a card.