Transmat Actuator

A smooth, palm-sized disc of polished metal hums faintly as it activates, its edges curving inward slightly to fit a hand’s grip. The Castellan presses it into the Master’s palm with a word, its surface warm for only a moment before cooling to the touch. It is not the transmat itself but the key that triggers it, seized by Borusa in the aftermath of the Master’s departure—a silent reassertion of time-lord authority.