Mishra, Eminent One, Gonti's Aether Heart, and Delina, Wild Mage

Prerequisites

• Mishra, Eminent One on the battlefield
• Gonti's Aether Heart on the battlefield
• Delina, Wild Mage on the battlefield
• Delina does not have summoning sickness
• An opponent cannot block and kill Delina

Steps

1. At the beginning of your combat phase, Mishra triggers, creating a 4/4 artifact creature token copy of Gonti's Aether Heart named Mishra's Warform
2. When Mishra's Warform enters the battlefield, it and Gonti's Aether Heart trigger, causing you to get four energy counters
3. Declare Delina as an attacker
4. Delina triggers, creating at least one nonlegendary token copy of Mishra's Warform that is tapped and attacking
5. When the nonlegendary Mishra's Warform enters the battlefield, it, the legendary Mishra's Warform, and Gonti's Aether Heart trigger, causing you to get six energy counters
6. Activate a Mishra's Warform by paying eight energy counters and exiling it, causing you to take an extra turn after this one
7. Repeat each turn

Results

• Infinite turns