Time Sieve, Encroaching Mycosynth, Rionya, Fire Dancer, and Abhorrent Overlord

Prerequisites

• Time Sieve on the battlefield
• Encroaching Mycosynth on the battlefield
• Rionya, Fire Dancer on the battlefield
• Abhorrent Overlord on the battlefield

Steps

1. At the beginning of your combat phase, Rionya triggers, creating at least one token copy of Abhorrent Overlord with haste
2. When the Abhorrent Overlord token enters the battlefield, it triggers, creating at least four 1/1 Harpy creature tokens
3. Activate Time Sieve by tapping it, sacrificing the Abhorrent Overlord token and the Harpy tokens, causing you to take an extra turn after this one
4. Repeat each turn

Results

• Infinite turns