Mirror-Mad Phantasm, and Polymorphous Rush

Prerequisites

• Mirror-Mad Phantasm on the battlefield
• Polymorphous Rush in hand
• You control at least one additional creature
• available

Steps

1. Cast Polymorphous Rush by paying , causing another creature you control to become a copy of Mirror-Mad Phantasm until end of turn
2. Activate the creature by paying , shuffling it into your library and milling your entire library due to it not having a card named Mirror-Mad Phantasm in it

Results

• Infinite self-mill