Agatha's Soul Cauldron, Siren of the Silent Song, and Aphetto Alchemist

Prerequisites

• Agatha's Soul Cauldron on the battlefield
• Siren of the Silent Song on the battlefield
• Aphetto Alchemist in exile

Steps

1. Activate Siren of the Silent Song using Aphetto Alchemist's ability by tapping it, untapping Siren of the Silent Song Siren of the Silent Song triggers, causing each opponent to discard and mill a card
2. Repeat

Results

• Infinite mill