Spring-heeled Jack

Spring-heeled Jack was a Hunter.

Searching for Morjanus
Jack was sent to Earth to kill Morjanus in 1837. He was unable to find her as she had taken on a false identity. He was called Spring-heeled Jack because he jumped around. He roamed London for three years, trying to find Morjanus. He captured many women and searched them for a necklace that would identify them as Morjanus.

Meeting the Doctor
In 1840, while trying to search Penny Chapman, Jack was attacked by the Eighth Doctor, who shoved a cart at him. This did not hurt Jack, who fled. He followed the Doctor and Penny to her home. When the Doctor was alone he unleashed a blast of psychic energy upon him. He saw the Doctor's thoughts and the Doctor used the blast to see Jack's. Jack thought of his burning home planet and his dying people. Penny attacked Jack with a shotgun, but to no effect. Jack left.

Guardian Demon
Jack found Morjanus disguised as Penny and used his psychic attack on her. He killed a part of her that was Morjanus but left Penny alive. He remained in London as its "Guardian Demon" declaring that his home planet was wonderful but had gone. (DWM: The Curious Tale of Spring-Heeled Jack)

Personality
Jack went mad searching for Morjanus. He always spoke in rhyme. He liked to scare people and often threatened them with his attacks. (DWM: The Curious Tale of Spring-Heeled Jack)