The Everfocus Lens

When The Everfocus Lens enters the battlefield, choose one creature and one non-creature card under your control. Every opponent may choose one creature under their control as well. All cards chosen are attached to The Everfocus Lens. Put 10 time counters on The Everfocus Lens. Remove a time counter at the end of your turn.
When The Everfocus Lens has no time counters left, destroy every card on the board. All cards attached to The Everfocus Lens go back to their controllers tapped.