Medomai the Ageless, Identity Thief, and Mirror Box

Prerequisites

• Medomai the Ageless on the battlefield
• Identity Thief on the battlefield
• Mirror Box on the battlefield
• Identity Thief does not have summoning sickness
• An opponent is unable to block and kill Identity Thief

Steps

1. Declare Identity Thief as an attacker
2. Identity Thief triggers, exiling Medomai and causing Identity Thief to become a copy of Medomai until end of turn
3. Deal combat damage to an opponent using Identity Thief
4. Identity Thief triggers, causing you to take an extra turn after this one
5. At the beginning of your end step, Identity Thief triggers, returning Medomai from exile to the battlefield
6. During your cleanup step, Identity Thief stops being a copy of Medomai
7. Repeat each turn

Results

• Infinite turns