Displacer Kitten | Molten-Core Maestro | Storm-Kiln Artist (and one other card)

Cards

Cast the copy of
Stream of Life from exile for X=4 by paying ({4} magic symbol) ({G} magic symbol) .
When you cast that spell,
Molten-Core Maestro,
Storm-Kiln Artist, and
Displacer Kitten trigger.
Resolve the
Displacer Kitten trigger, blinking
Infirmary Healer, which enters prepared.
Resolve the
Molten-Core Maestro trigger, putting a +1/+1 counter on it and adding an amount of ({R} magic symbol) equal to its power.
Resolve the
Storm-Kiln Artist trigger, creating a Treasure token.
Activate the Treasure token by tapping and sacrificing it, adding the one non-red mana you need to cast the spell from step 1.
Resolve the spell from step 1.
Repeat.
Cast a copy of the prepared spell from exile by paying one mana, unpreparing
Infirmary Healer // Stream of Life.
When you cast this,
Displacer Kitten and
Storm-Kiln Artist triggers.
Resolve the
Displacer Kitten ability, flickering
Infirmary Healer // Stream of Life, which enters prepared.
Resolve the remaining trigger, creating a Treasure token.
Resolve the spell from step 1.
Activate the Treasure token by tapping and sacrificing it, adding one mana.
Repeat.

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