Orvar, the All-Form | Storm-Kiln Artist | Sea Gate Stormcaller

(and one other card)

Cast
Sea Gate Stormcaller by paying ({1} magic symbol) ({U} magic symbol) .
Sea Gate Stormcaller enters the battlefield, copying the next instant or sorcery spell you cast with mana value two or less.
Cast
Unsubstantiate by paying ({1} magic symbol) ({U} magic symbol) , targeting
Sea Gate Stormcaller.
Sea Gate Stormcaller,
Orvar, and
Storm-Kiln Artist trigger.
Resolve the
Sea Gate Stormcaller trigger, copying
Unsubstantiate, targeting the original
Unsubstantiate.
Storm-Kiln Artist triggers, creating a Treasure token.
Resolve the copy of
Unsubstantiate, returning the original
Unsubstantiate to your hand.
Resolve the
Orvar trigger, creating a token copy of
Sea Gate Stormcaller.
The
Sea Gate Stormcaller token enters the battlefield, copying the next instant or sorcery spell you cast with mana value two or less.
Resolve the
Storm-Kiln Artist trigger from step 4, creating a Treasure token.
Activate both Treasure tokens by tapping and sacrificing them, adding ({U} magic symbol) ({U} magic symbol) .
Repeat from step 3.