Unglued

Volrath's Motion Sensor

When Volrath's Motion Sensor comes into play, choose target hand controlled by an opponent. Enchanted player balances Volrath's Motion Sensor on the back of that hand.
If Volrath's Motion Sensor falls off the hand, sacrifice Volrath's Motion Sensor and that player loses 3 life.

Enchant player
As Volrath's Motion Sensor enters, choose one of enchanted player's hands. That player balances Volrath's Motion Sensor on the back of that hand.
When Volrath's Motion Sensor falls off the chosen hand, sacrifice Volrath's Motion Sensor and enchanted player loses 3 life.