Orah, Skyclave Hierophant, Sister Hospitaller, Ancestor's Chosen, and Umbral Collar Zealot

Prerequisites

• Orah, Skyclave Hierophant on the battlefield
• Sister Hospitaller in the graveyard
• Ancestor's Chosen on the battlefield
• Umbral Collar Zealot on the battlefield

Steps

1. Activate Umbral Collar Zealot by sacrificing Ancestor's Chosen
2. When Ancestor's Chosen dies, Orah triggers, returning Sister Hospitaller from your graveyard to the battlefield
3. When Sister Hospitaller enters, it triggers, returning Ancestor's Chosen from your graveyard to the battlefield and causing you to gain 7 life
4. When Ancestor's Chosen enters, it triggers, causing you to gain 1 life for each card in your graveyard
5. Resolve the Umbral Collar Zealot ability
6. Activate Umbral Collar Zealot by sacrificing Sister Hospitaller
7. When Sister Hospitaller dies, Orah triggers, allowing you to return a Cleric with mana value 5 or less from your graveyard to the battlefield
8. Resolve the Umbral Collar Zealot ability
9. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite lifegain
• Infinite lifegain triggers
• Infinite recursion of some creature cards in your graveyard
• Infinite sacrifice triggers
• Infinite surveil