Havi, the All-Father, Gerrard, Weatherlight Hero, and Thermopod

Prerequisites

• Havi, the All-Father on the battlefield
• Gerrard, Weatherlight Hero on the battlefield
• Thermopod on the battlefield
• undefined

Steps

1. Activate Thermopod by sacrificing Gerrard, adding
2. When Gerrard dies, it and Havi trigger
3. Resolve the Havi trigger, returning up to one legendary creature card with mana value 3 or less from your graveyard to the battlefield
4. Holding priority, activate Thermopod by sacrificing Havi, adding
5. When Havi dies, it triggers, returning Gerrard from your graveyard to the battlefield
6. Resolve the Gerrard trigger from step 2, failing to exile it as it is no longer in your graveyard and returning Havi from your graveyard to the battlefield
7. Repeat

Results

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