Magar of the Magic Strings, and Time Stretch

Prerequisites

• Magar of the Magic Strings on the battlefield
• Time Stretch in hand
• available

Steps

1. Cast Time Stretch by paying its mana cost, causing you to take two extra turns after this one
2. Activate Magar by paying , noting Time Stretch and putting it face down as a 3/3 creature
3. Move to your second extra turn
4. Deal combat damage to an opponent with the face down creature
5. The face down creature triggers, causing you to cast a copy of Time Stretch without paying its mana cost
6. Resolve the copy of Time Stretch, causing you to take two extra turns after this one
7. Repeat from step 3

Results

• Infinite turns