msem-instigator

Destroy target artifact or nonbasic land. Its controller creates a colorless artifact token named Lotus Petal with “{T}, Sacrifice this artifact: Add one mana of any color.”

This spell costs {2} less to cast if you control a legendary creature.
Search your library for a creature or land card, reveal it, put it into your hand, then shuffle.

Haste
Storm Entity enters with a +1/+1 counter on it for each other spell cast this turn.

Whenever a permanent you control becomes tapped, Storm Servant gets +1/+1 until end of turn.

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.

Colossal 3—{4}{R} (You may cast this for its colossal cost to have it enter with three +1/+1 counters; or pay {4}{R} as a sorcery: Put three +1/+1 counters on it if it has none.)
When Storm-Eye Salamander's colossal ability puts one or more counters on it, exile the top three cards of your library. Until the end of your next turn, you may play one of those cards.

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.

Other artifacts you control have ward {1}.
Overcast — Whenever you cast an artifact creature spell, if {C} was spent to cast it, it enters with an additional +1/+1 counter on it.

Prowess, haste

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.)

{1}, {T}: Surveil 1. (Look at the top card of your library. You may put that card into your graveyard.)
{2}, {T}, Exile an instant or sorcery card from your graveyard: Stormvolt Apprentice deals 1 damage to each opponent.

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

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

Prowess
Pay 2 life: Change a target of target spell or ability to Straw Intellectual.

Creatures blocking or blocked by Straw Officer have wither. (They deal damage to creatures in the form of -1/-1 counters.)

As Straw Simulacrum enters, choose a creature type.
Straw Simulacrum is the chosen creature type in addition to its other types.
Other creatures you control of the chosen type get +1/+1.

Whenever another creature you control enters, put your choice of a +1/+1 counter, a trample counter, or a haste counter on it.

Stray Sighthound can't be blocked by creatures with power 2 or less.
Attain {3}{G} ({3}{G}: Transform this. Spend at least three colors of mana to activate this, and only as a sorcery.)

At the beginning of your end step, if you control two or more tapped creatures, exile the top card of your library. Until the end of your next turn, you may play that card.

Menace
Deploy 4 (As this enters, you may tap any number of other creatures you control with total power 4 or more.)
When Street Raider enters deployed, discard your hand, then draw three cards.

Harmony — Target creature gains haste until end of turn.
When Streetside Entertainer enters, harmonize. (Trigger up to one harmony of one permanent you control.)

Scry 3, then reveal the top card of your library. Target creature gains trample and gets +X/+X until end of turn, where X is that card's mana value.