Mikaeus, the Unhallowed, Krark-Clan Grunt, and Grim Poppet

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Krark-Clan Grunt on the battlefield
• Grim Poppet on the battlefield

Steps

1. Activate Krark-Clan Grunt by sacrificing Grim Poppet
2. When Grim Poppet 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 Krark-Clan Grunt ability Repeat

Results

• Infinite LTB
• Infinite ETB
• Infinite sacrifice triggers
• Infinite death triggers
• Infinite -1/-1 counters
• Infinitely powerful creature until end of turn