Umbral Collar Zealot, Wingrattle Scarecrow, and Thran Vigil

Prerequisites

• Umbral Collar Zealot on the battlefield
• Wingrattle Scarecrow on the battlefield
• Thran Vigil on the battlefield

Steps

1. Activate Umbral Collar Zealot by sacrificing Wingrattle Scarecrow
2. When Wingrattle Scarecrow dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
3. Thran Vigil triggers, putting a +1/+1 counter on Wingrattle Scarecrow
4. Resolve the Umbral Collar Zealot ability
5. Repeat

Results

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