Magosi, the Waterveil, The Ozolith, Nature's Revolt, and Contagion Engine

Prerequisites

• Magosi, the Waterveil on the battlefield
• The Ozolith on the battlefield
• Nature's Revolt on the battlefield
• Contagion Engine on the battlefield
• Magosi has at least one eon counter on it and does not have summoning sickness
• It is your precombat main phase
• each turn available

Steps

1. During your precombat main phase, activate Contagion Engine by paying and tapping it, putting two eon counters on Magosi
2. Activate Magosi's third ability by tapping it, removing an eon counter from it and returning it from the battlefield to your hand
3. When Magosi leaves the battlefield, The Ozolith's first ability triggers, putting an eon counter on The Ozolith
4. Resolve the Magosi ability, causing you to take an extra turn after this one
5. Play Magosi
6. At the beginning of your combat phase, The Ozolith triggers, putting two eon counters on Magosi
7. Repeat each turn

Results

• Infinite turns