Eye of Jace

At the beginning of your upkeep, surveil 1. Then if there are seven or more cards in your graveyard, sacrifice this artifact, it deals 2 damage to each opponent, and you gain 2 life. (To surveil 1, look at the top card of your library. You may put it into your graveyard.)

All cadets wore the Eye. None discussed how it followed their every move.