Magosi, the Waterveil, Adric, Mathematical Genius, and North Pole Patrol

Prerequisites

• Magosi, the Waterveil on the battlefield
• Adric, Mathematical Genius on the battlefield
• North Pole Patrol on the battlefield
• each turn available

Steps

1. Activate Magosi's second activated ability by paying and tapping it, putting an eon counter on Magosi and skipping your next turn
2. Activate North Pole Patrol by tapping it, untapping Magosi
3. Activate Magosi's third activated ability by tapping it, removing an eon counter from it, and returning it to your hand
4. Holding priority, activate Adric by paying and tapping it, copying Magosi's ability
5. Resolve both instances of Magosi's ability, causing you to take two extra turns after this one
6. Play Magosi
7. Move to your second extra turn
8. The first extra turn will be skipped due to the ability activated in step 1
9. Repeat

Results

• Infinite turns
• Lock