Soulherder, Eternal Witness, and Time Stretch

Prerequisites

• Soulherder on the battlefield
• Eternal Witness on the battlefield
• Time Stretch in hand
• every other turn available

Steps

1. With Soulherder and a creature based spell recursion effect on the battlefield, cast the extra turn spell
2. Move to end step and target the creature with Soulherder's ability
3. When creature re-enters the battlefield, target the extra turn spell in your graveyard and return it to your hand, then pass to yourself
4. Repeat

Results

• Infinite turns