Thor, God of Thunder, Time Stretch, and Meneldor, Swift Savior

Prerequisites

• Thor, God of Thunder on the battlefield
• Time Stretch in hand
• Meneldor, Swift Savior on the battlefield
• each other turn available

Steps

1. Cast Time Stretch by paying its mana cost
2. Thor's second ability triggers, dealing damage to any target
3. Resolve Time Stretch, causing you to take two extra turns after this one
4. Blink Thor using Meneldor
5. When Thor enters, it triggers, allowing you to cast Time Stretch from your graveyard until the end of your next turn
6. Move to your second extra turn
7. Cast Time Stretch from your graveyard by paying its mana cost
8. Repeat from step 2

Results

• Infinite turns
• Lock