The Sycorax whip was a weapon in possession of Fadros Pallujikaa.
Properties
The Sycorax whip resembled a brown rope with a handle housing the micro-fusion generator. When used with intent to kill, it would do so by means of the wielder pulling it back, followed by suddenly throwing the end at a human's neck. During this process, the rope would illuminate blue and show the victims bones in the same colour, similar to a Dalek's death ray. This destroyed all cells in the human body as well as disintegrating clothes, leaving only scorched bones behind. (TV: The Christmas Invasion)
History
During the Sycorax invasion of Earth on Christmas 2006, Pallujikaa used his whip to murder Daniel Llewellyn and Richard Blake, who were part of a delegation of humans he had teleported aboard his ship. Shortly afterwards, he attempted to reproduce the results on the newly-regenerated Tenth Doctor, who had emerged from the TARDIS, only for the the latter to grab the whip a split-second before it came into contact with his neck. (TV: The Christmas Invasion)