Progenitor Mimic + Time Stretch + Izzet Chronarch

Progenitor Mimic

Time Stretch

Izzet Chronarch

How it works

1. Cast Time Stretch by paying 8, taking two extra turns after this one.
2. At the beginning of your next upkeep, Progenitor Mimic triggers, creating a token copy of Izzet Chronarch.
3. When the token Izzet Chronarch enters the battlefield, it triggers itself, returning Time Stretch from your graveyard to your hand.
4. Repeat.

This mesmerizing loop uses Progenitor Mimic as a tireless engine, casting Time Stretch to seize infinite turns while utilizing Izzet Chronarch to endlessly recycle the sorcery back to your hand. Because Progenitor Mimic is a non-token copy of Izzet Chronarch (or a clone of it that avoids token status initially), its upkeep trigger dutifully manufactures a fresh Izzet Chronarch token every turn. Each newly birthed token immediately triggers its own enters-the-battlefield ability to fish Time Stretch right back out of the graveyard, locking down the game in an unstoppable succession of extra turns.