Optimus Prime, Hero // Optimus Prime, Autobot Leader, Mikaeus, the Unhallowed, and Yahenni, Undying Partisan

Prerequisites

• Optimus Prime, Hero // Optimus Prime, Autobot Leader on the battlefield
• Mikaeus, the Unhallowed on the battlefield
• Yahenni, Undying Partisan on the battlefield
• It is your turn

Steps

1. Activate Yahenni by sacrificing Optimus Prime, Hero
2. When Optimus Prime, Hero dies, its second ability triggers, returning it from your graveyard to the battlefield as Optimus Prime, Autobot Leader
3. Activate Yahenni by sacrificing Optimus Prime, Autobot Leader
4. When Optimus Prime, Autobot Leader dies, Mikaeus triggers, returning Optimus Prime from your graveyard to the battlefield as Optimus Prime, Hero with a +1/+1 counter on it
5. Resolve both Yahenni abilities from steps 1 and 3
6. Repeat

Results

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