Spiritcall Enthusiast // Scrollboost | Stormsplitter

Cards

({3} magic symbol) ({W} magic symbol) plus the cost of the additional instant or sorcery available.

Cast any instant or sorcery by paying its cost.
Stormsplitter triggers, creating a token copy of itself.
When that token enters,
Spiritcall Enthusiast triggers, becoming prepared.
Resolve the instant or sorcery from step 1.
Cast a copy of
Scrollboost from exile by paying ({1} magic symbol) ({W} magic symbol) and unpreparing
Spiritcall Enthusiast.
Both
Stormsplitters trigger, creating two more token copies of
Stormsplitter.
When a token enters,
Spiritcall Enthusiast triggers, becoming prepared.
Resolve the copy of
Scrollboost, giving one or two creatures +2/+2 until end of turn.
Activate
Phyrexian Altar by sacrificing one
Stormsplitter token, adding ({W} magic symbol) .
Activate any mana source, adding an additional ({1} magic symbol) .
Cast a copy of
Scrollboost from exile by paying ({1} magic symbol) ({W} magic symbol) and unpreparing
Spiritcall Enthusiast.
At least three
Stormsplitters trigger, creating at least three more token copies of
Stormsplitter.
When a token enters,
Spiritcall Enthusiast triggers, becoming prepared.
Resolve the copy of
Scrollboost, giving one or two creatures +2/+2 until end of turn.
Activate
Phyrexian Altar by sacrificing two
Stormsplitter tokens, adding ({W} magic symbol) ({W} magic symbol) .
Repeat from step 11 any number of times.
Once you have infinite
Stormsplitter tokens, you may activate
Phyrexian Altar any number of times, adding infinite mana.

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