Echocasting Symposium, Myr Battlesphere, and Time Sieve

Prerequisites

• Echocasting Symposium in hand
• Myr Battlesphere on the battlefield
• Time Sieve on the battlefield
• available

Steps

1. Cast Echocasting Symposium by paying , creating a token copy of Myr Battlesphere and exiling Echocasting Symposium
2. When Myr Battlesphere enters, it triggers, creating four 1/1 Myr artifact creature tokens
3. Activate Time Sieve by tapping it, sacrificing the Myr Battlesphere token and the four Myr tokens, causing you to take an extra turn after this one
4. Move to your next turn
5. At the beginning of your precombat main phase, Echocasting Symposium's paradigm ability triggers, causing you to cast a copy of it from exile
6. Resolve the copy, creating a token copy of Myr Battlesphere
7. Repeat from step 2

Results

• Lock
• Infinite turns