Rootha, Mercurial Artist | Seething Song | Storm-Kiln Artist (and one other card)

Cards

Activate
Winding Canyons by paying ({2} magic symbol) and tapping it, allowing you to cast creature spells as though they have flash this turn.
Cast
Seething Song by paying ({2} magic symbol) ({R} magic symbol) .
Storm-Kiln Artist triggers, creating a Treasure token.
Activate a Treasure by tapping and sacrificing it, adding ({1} magic symbol) .
Holding priority, activate
Rootha by paying ({2} magic symbol) and returning it from the battlefield to your hand, copying
Seething Song.
Storm-Kiln Artist triggers, creating a Treasure token.
Resolve the
Seething Song copy, adding ({R} magic symbol) ({R} magic symbol) ({R} magic symbol) ({R} magic symbol) ({R} magic symbol) .
Activate a Treasure by tapping and sacrificing it, adding ({U} magic symbol) .
Cast
Rootha by paying ({1} magic symbol) ({U} magic symbol) ({R} magic symbol) .
Repeat from step 5.

This combo has been estimated to be Exhibition (Bracket 1+).