Colony Sarff
Colony Sarff was a snake-like creature who searched for the Doctor by order of the dying Davros. Sarff first went to the Maldovarium to ask where the Doctor was; he then went to the Shadow Proclamation for the same reason. Sarff traveled next to Karn and encountered the Sisterhood of Karn; he was unable to use his powers against them. Colony Sarff told Ohila, the Sisterhood's High Priestess, that Davros wanted to see the Doctor and departed. The Doctor was present to hear this. Sarff returned to Davros, who told him to look to the Doctor's friends in order to find the Time Lord. He followed Missy, arriving in 1138, Essex. One of his snakes attacked Bors, before returned to him. He took the Doctor with him to his spaceship, however as Missy and Clara asked he took them with him to Skaro. He took the Doctor to Davros, who asked him to leave. (TV: The Magician's Apprentice)