Wormfang Manta, Doorkeeper Thrull, and Baboon Spirit

Prerequisites

• Wormfang Manta on the battlefield
• Doorkeeper Thrull on the battlefield
• Baboon Spirit in hand or on the battlefield
• each turn available

Steps

1. Blink Wormfang Manta using Baboon Spirit
2. Wormfang Manta's first ability won't trigger due to Doorkeeper Thrull
3. Wormfang Manta's second ability triggers, causing you to take an extra turn after this one
4. Repeat each turn

Results

• Infinite turns
• Lock