Sage of Hours, Cathars' Crusade, Myr Battlesphere, and Soulherder

Prerequisites

• Sage of Hours on the battlefield
• Cathars' Crusade on the battlefield
• Myr Battlesphere on the battlefield
• Soulherder on the battlefield

Steps

1. At the beginning of your end step, Soulherder triggers, blinking Myr Battlesphere
2. Soulherder triggers, putting a +1/+1 counter on itself
3. Myr Battlesphere enters the battlefield, triggering itself and Cathars' Crusade
4. Resolve the Myr Battlesphere trigger, creating four 1/1 Myr creature tokens
5. The Myr tokens enter the battlefield, triggering Cathars' Crusade four times
6. Resolve all Cathars' Crusade triggers, putting five +1/+1 counters on each creature you control
7. Activate Sage of Hours by removing all +1/+1 counters from it, causing you to take at least one extra turn after this one
8. Repeat each turn

Results

• Infinite turns