Prosper, Tome-Bound, Eternal Scourge, Ashnod's Altar, and Mimic Vat

Prerequisites

• Prosper, Tome-Bound on the battlefield
• Eternal Scourge on the battlefield
• Ashnod's Altar on the battlefield
• Mimic Vat on the battlefield
• available

Steps

1. Activate Ashnod's Altar by sacrificing Eternal Scourge, adding
2. Mimic Vat's imprint ability triggers, exiling Eternal Scourge and returning any previously exiled creatures to their owners' graveyards
3. Cast Eternal Scourge for
4. Prosper triggers, creating a Treasure token
5. Resolve Eternal Scourge, allowing it to enter the battlefield
6. Activate the Treasure token by tapping and sacrificing it, adding one mana of any color
7. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers