Morophon, the Boundless, Whitemane Lion, and Leyline of Mutation

Prerequisites

• Morophon, the Boundless on the battlefield
• Whitemane Lion in hand
• Leyline of Mutation on the battlefield

Steps

1. Cast Whitemane Lion by paying
2. When Whitemane Lion enters, it triggers, returning itself from the battlefield to your hand
3. Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite storm count