Dr. Walter Bishop : [to Peter] You are my very favorite thing.
Dr. Walter Bishop : Peter, hold on to these tight. Anti-gravity osmium bullets. Shoot Observers with these and watch them float away like balloons.
Peter Bishop : If we shoot 'em, they're dead. Why'd we want 'em to float away?
Dr. Walter Bishop : ...Because it's cool.
Peter Bishop : That makes sense Walter.