Metamorphosis Fanatic, All-Fates Stalker, and Yahenni, Undying Partisan

Prerequisites

• Metamorphosis Fanatic in hand
• All-Fates Stalker 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 All-Fates Stalker from your graveyard to the battlefield
3. When All-Fates Stalker enters, it triggers, exiling Metamorphosis Fanatic until All-Fates Stalker leaves the battlefield
4. Activate Yahenni by sacrificing All-Fates Stalker
5. When All-Fates Stalker 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