Mindslaver +Lighthouse Chronologist +Academy Ruins +

Soft lock Infinite turns Revised by CR

Lighthouse Chronologist must be on Level 7 or greater. Activate Mindslaver to take control of your opponent's turn. Play your opponent's turn. On the end step, Lighthouse Chronologist's ability will trigger, and you'll gain an extra turn. Use the extra turn to return Mindslaver to the top of your deck with Academy Ruins and use the other turn to cast and activate Mindslaver Repeat the process.

Legallity