No one on the field could hide from Mercury's electronic visor. Scanning the area for other patients, she spotted the outline of a girl near the building.

"Mercury...shabon...spray," she said, drawing on her power of ice to send forth the icy mist to roll across and blanket the field completely. She hoped the sharp drop in temperature would pursuade the patient to go back inside, like it had the other two. If not...well she had the ability to detect where the other was in lowered visibility.