Mikaeus, the Unhallowed, Umbral Collar Zealot, and Chainbreaker

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Umbral Collar Zealot on the battlefield
• Chainbreaker on the battlefield

Steps

1. Activate Umbral Collar Zealot by sacrificing Chainbreaker
2. When Chainbreaker dies, its undying ability triggers, returning it from your graveyard to the battlefield without a +1/+1 counter on it due to its replacement effect
3. Resolve the Umbral Collar Zealot ability Repeat

Results

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