Cast a copy of Seething Song by paying {2}{R}.
Displacer Kitten triggers, blinking Blazing Firesinger. It'll enter prepared due to its effect.
Resolve Seething Song, adding {R}{R}{R}{R}{R}.
Repeat.

Infinite ETB

Infinite LTB

Infinite magecraft triggers

Infinite red mana

Infinite storm count

Blazing Firesinger // Seething Song

Displacer Kitten

Cast a copy of Seething Song from exile by paying no more than {1}{R}, adding {R}{R}{R}{R}{R}.
When you cast that spell, Storm-Kiln Artist triggers, creating a Treasure token.
Activate the Treasure token by tapping and sacrificing it, adding one mana of any color.
Activate Emiel the Blessed by paying {3}, blinking Blazing Firesinger, which enters prepared.
Repeat.

Emiel the Blessed

Storm-Kiln Artist

Activate Kiki-Jiki by tapping it, copying Blazing Firesinger. It'll enter prepared due to its effect.
Cast a copy of Seething Song by paying {1}{R} due to Stone Calendar.
Hematite Talisman triggers, causing you to pay {3} to untap Kiki-Jiki.
Resolve Seething Song, adding {R}{R}{R}{R}{R}.
Repeat.

Infinite creature tokens with haste

Infinite death triggers

Infinite sacrifice triggers

Kiki-Jiki, Mirror Breaker

Hematite Talisman

Stone Calendar

Activate Kiki-Jiki by tapping it, copying Blazing Firesinger. It'll enter prepared due to its effect.
Cast a copy of Seething Song by paying {2}{R}.
Thousand-Year Storm and Hematite Talisman trigger.
Resolve the Thousand-Year Storm trigger, copying Seething Song for each instant and sorcery cast before it this turn.
Resolve all copies of Seething Song, adding {R}{R}{R}{R}{R} for each copy.
Resolve the Hematite Talisman trigger, causing you to pay {3} to untap Kiki-Jiki.
Resolve the original Seething Song, adding {R}{R}{R}{R}{R}.
Repeat.

Thousand-Year Storm

Combos with "Blazing Firesinger // Seething Song"