Combat Celebrant, Adarkar Valkyrie, Anger, and Ashnod's Altar

Prerequisites

• Combat Celebrant on the battlefield
• Adarkar Valkyrie on the battlefield
• Anger in the graveyard
• Ashnod's Altar on the battlefield
• You control a Mountain

Steps

1. Activate Adarkar Valkyrie by tapping it, targeting Combat Celebrant
2. Declare Combat Celebrant as an attacker, choosing to exert it as it attacks
3. Combat Celebrant triggers, untapping all other creatures you control and causing you to get an additional combat phase after this one
4. Activate Ashnod's Altar by sacrificing Combat Celebrant, adding
5. Combat Celebrant dies, triggering Adarkar Valkyrie, returning Combat Celebrant from your graveyard to the battlefield
6. Repeat

Results

• Infinite combat phases
• Infinite death triggers
• Infinite ETB
• Infinite LTB
• Infinite sacrifice triggers