Mikaeus, the Unhallowed, Grim Poppet, and Carrion Feeder

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Grim Poppet on the battlefield
• Carrion Feeder on the battlefield

Steps

1. Activate Carrion Feeder by sacrificing Grim Poppet
2. Grim Poppet dies, triggering its undying ability, returning it from your graveyard to the battlefield with two -1/-1 counters on it
3. Resolve the Carrion Feeder ability, putting a +1/+1 counter on it
4. Repeat

Results

• Infinite -1/-1 counters
• Infinite +1/+1 counters on Carrion Feeder
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers