Wormfang Manta, The Neutrinos, and Karn, Argent Defender

Prerequisites

• Wormfang Manta on the battlefield
• The Neutrinos on the battlefield
• Karn, Argent Defender on the battlefield

Steps

1. Declare The Neutrinos as an attacker, attacking a player who cannot kill it in combat
2. When The Neutrinos attacks, it triggers, exiling and returning (tapped and attacking) Wormfang Manta
3. When Wormfang Manta leaves the battlefield, its second ability triggers, causing you to take an extra turn after this one
4. Wormfang Manta entering does not cause its abillity to trigger due to Karn
5. Repeat each turn

Results

• Infinite turns
• Lock