Pietro ought to have known better, ought to have known exactly what a raging Magneto was capable of. For now he would wait, reign himself in, let them miss Pietro before he went to make the exchange. Once that was accomplished he would kill them all.
Wordlessly he twirled his fingers and several more bands formed, around his ankles and his wrists. Magnus left him for a few minutes and returned with two people Pietro didn't recognize. "Take him below," he instructed them. "See that he's secure." He didn't look at his son again as he went back to the window and stared out through the glass, looking for all the world as if the conversation had never taken place.