Cause Unlicensed Hearse to become a creature.
Activate Thornbite Staff's equip ability by paying {4}, attaching it to Unlicensed Hearse.
Activate Ashnod's Altar by sacrificing Eternal Scourge, adding {C}{C}.
Eternal Scourge dies, triggering Unlicensed Hearse, untapping Unlicensed Hearse.
Activate Unlicensed Hearse by tapping it, exiling Eternal Scourge from your graveyard.
Cast Eternal Scourge from exile by paying {1}.
Repeat from step 3.

Infinite colorless mana

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Infinite storm count

Unlicensed Hearse

Eternal Scourge

Ashnod's Altar

Thornbite Staff

Ugin, the Ineffable

Cause Unlicensed Hearse to become a creature.
Activate Thornbite Staff's equip ability by paying {4}, attaching it to Unlicensed Hearse.
Activate Ashnod's Altar by sacrificing Eternal Scourge, adding {C}{C}.
Eternal Scourge dies, triggering Unlicensed Hearse, untapping Unlicensed Hearse.
Activate Unlicensed Hearse by tapping it, exiling Eternal Scourge from your graveyard.
Cast Eternal Scourge from exile by paying {3}.
Prosper triggers, creating a Treasure token.
Activate the Treasure token by tapping and sacrificing it, adding {1}.
Repeat from step 3.

Infinite artifact ETB

Prosper, Tome-Bound

Eye of Ugin

Urza's Incubator

Combos with "Unlicensed Hearse"