Missy's device

Missy's Device was a piece of multi-purpose technology owned by the Master in her female form.

She used the device to vapourise individuals, including Dr Chang, Seb and Osgood. It was also capable of taking photographs, or selfies. (TV: Dark Water, Death in Heaven)

The device later fell into the hands of Clara Oswald, who was prepared to use it to kill Missy out of revenge for what happened to Danny Pink - her boyfriend. The Twelfth Doctor took the device from her and told her that he would save her by doing the deed himself. Instead, Missy was shot from afar by the Brigadier in Cyberman form. (TV: Death in Heaven)