Mikaeus, the Unhallowed, Thermopod, and Trapjaw Kelpie

Prerequisites

• Mikaeus, the Unhallowed on the battlefield
• Thermopod on the battlefield
• Trapjaw Kelpie on the battlefield

Steps

1. Activate Thermopod by sacrificing Trapjaw Kelpie
2. When Trapjaw Kelpie dies, its persist ability triggers, returning it from your graveyard to the battlefield with a -1/-1 counter on it
3. Activate Thermopod by sacrificing Trapjaw Kelpie
4. When Trapjaw Kelpie dies, its undying ability triggers, returning it from your graveyard to the battlefield with a +1/+1 counter on it
5. Repeat

Results

• Infinite ETB
• Infinite LTB
• Infinite death triggers
• Infinite red mana
• Infinite sacrifice triggers