Sage of Hours, Cathars' Crusade, Myr Battlesphere, and Conjurer's Closet

Prerequisites

• Sage of Hours on the battlefield
• Cathars' Crusade on the battlefield
• Myr Battlesphere on the battlefield
• Conjurer's Closet on the battlefield

Steps

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

Results

• Infinite turns