Umbral Collar Zealot, Faceless Butcher, and Angel of Indemnity

Prerequisites

• Umbral Collar Zealot on the battlefield
• Faceless Butcher in hand
• Angel of Indemnity on the battlefield
• available

Steps

1. Cast Faceless Butcher by paying its mana cost
2. When Faceless Butcher enters, its first ability triggers, exiling Angel of Indemnity
3. Activate Umbral Collar Zealot by sacrificing Faceless Butcher
4. When Faceless Butcher dies, its second ability triggers, returning Angel of Indemnity from exile to the battlefield
5. When Angel of Indemnity enters, it triggers, returning Faceless Butcher from your graveyard to the battlefield
6. When Faceless Butcher enters, its first ability triggers, exiling Angel of Indemnity
7. Resolve the Umbral Collar Zealot ability
8. Repeat from step 3

Results

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