Koll, the Forgemaster, Deathrender, and Thermopod

Prerequisites

• Koll, the Forgemaster on the battlefield
• Deathrender on the battlefield
• Thermopod on the battlefield
• Deahrender attached to Thermopod

Steps

1. Activate Thermopod's second ability by sacrificing it, adding
2. When Thermopod dies, Koll and Deathrender trigger
3. Resolve the Koll trigger, returning Thermopod from your graveyard to your hand
4. Resolve the Deathrender trigger, putting Thermopod from your hand onto the battlefield and attaching Deathrender to it
5. Repeat

Results

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