Phenax, God of Deception, Sewer Nemesis, and Terisian Mindbreaker

Prerequisites

• Phenax, God of Deception on the battlefield
• Sewer Nemesis on the battlefield
• Terisian Mindbreaker on the battlefield
• undefined

Steps

1. Declare Terisian Mindbreaker as an attacker attacking the opponent named by Sewer Nemesis
2. Terisian Mindbreaker triggers, causing the opponent to mill half their library, rounded up
3. Activate Sewer Nemesis by tapping it, causing the opponent to mill cards equal to the cards in their graveyard, milling the remainder of their library

Results

• Infinite mill for target opponent