Umbral Collar Zealot, and Warden of the Grove

Prerequisites

• Umbral Collar Zealot on the battlefield
• Warden of the Grove on the battlefield

Steps

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

Results

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