Death's Messenger

From Tardis Wiki, the free Doctor Who reference

Death's Messenger was a Krafayis which was sent by Death to the town of Slothe, on Gallifrey. After killing almost the entire population of the town, Death's Messenger retreated to a cave at the foot of Mount Perdition. Presus, the sole surviving member of Slothe, tracked down the Krafayis using using his shield as a mirror, and the two fought across the continent of Wild Endeavour until it was slain by Presus. (PROSE: Blind Fury)