Time Sieve, Myr Battlesphere, Soulherder, and Panharmonicon

Prerequisites

• Time Sieve on the battlefield
• Myr Battlesphere on the battlefield
• Soulherder on the battlefield
• Panharmonicon on the battlefield

Steps

1. At the beginning of your end step, Soulherder's second ability triggers, blinking Myr Battlesphere
2. Myr Battlesphere's first ability triggers twice and Soulherder's first ability triggers
3. Resolve the Soulherder trigger, putting a +1/+1 counter on it
4. Resolve both Myr Battlesphere triggers, creating eight 1/1 Myr artifact creature tokens
5. Activate Time Sieve by tapping it and sacrificing five Myrs, causing you to take an extra turn after this one
6. Repeat each turn

Results

• Infinite turns