Dalek Emperor (The Twelfth Doctor's been Timejacked!)

The Twelfth Doctor stated that a Dalek Emperor held leadership of the Daleks during his life. According to him, the Emperor had launched a plot to use the internet to convert the people of the 21st century into Dalek drones, which was something he needed to put a stop to "sooner or later". (WC: The Twelfth Doctor's been Timejacked!)