Progenitor Mimic, Time Warp, and Returned Pastcaller

Prerequisites

• Progenitor Mimic on the battlefield
• Time Warp on the battlefield
• Returned Pastcaller on the battlefield
• Enough mana available to cast the extra turn spell each turn
• Progenitor Mimic is a copy of Returned Pastcaller

Steps

1. Cast Time Warp by paying its mana cost, taking an extra turn after this one
2. At the beginning of your next upkeep, Progenitor Mimic triggers, creating a token copy of Returned Pastcaller
3. When the token Returned Pastcaller enters the battlefield, it triggers itself, returning Time Warp from your graveyard to your hand
4. Repeat

Results

• Infinite turns