Wildfire Eternal, Savage Beating, Helm of the Host, and Ardent Elementalist

Prerequisites

• Wildfire Eternal on the battlefield
• Savage Beating in the graveyard
• Helm of the Host on the battlefield
• Ardent Elementalist on the battlefield
• Wildfire Eternal does not have summoning sickness
• Helm of the Host attached to Ardent Elementalist
• An opponent cannot block Wildfire Eternal

Steps

1. At the beginning of your combat phase, Helm of the Host triggers, creating a token copy of Ardent Elementalist with haste
2. When the token Ardent Elementalist enters the battlefield, it triggers, returning Savage Beating to your hand from your graveyard
3. Declare Wildfire Eternal as an attacker
4. When Wildfire Eternal is not blocked, it triggers, casting Savage Beating from your hand without paying its mana cost
5. Resolve Savage Beating, causing you to untap all creatures you control and to get an additional combat phase after this one
6. Repeat each combat phase

Results

• Infinite combat phases
• Infinite creature tokens with haste
• Infinite ETB
• Infinite magecraft triggers
• Infinite mana creatures you control can produce
• Infinite storm count