Metamorphosis Fanatic, Lumbering Battlement, and Yahenni, Undying Partisan

Prerequisites

• Metamorphosis Fanatic in hand
• Lumbering Battlement in the graveyard
• Yahenni, Undying Partisan on the battlefield
• available

Steps

1. Cast Metamorphosis Fanatic by paying
2. When Metamorphosis Fanatic enters, it triggers, returning Lumbering Battlement from your graveyard to the battlefield
3. When Lumbering Battlement enters, it triggers, exiling Metamorphosis Fanatic until Lumbering Battlement leaves the battlefield
4. Activate Yahenni by sacrificing Lumbering Battlement
5. When Lumbering Battlement leaves the battlefield, Metamorphosis Fanatic is returned from exile to the battlefield
6. Repeat from step 2
7. Resolve all Yahenni abilities

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers