Chronology: Comic Book
Tecla Ibsen looks like a nice old lady, living peacefully with her husband Karl in Open Hill, the town where Eric Lyndon and his family moved. Karl Ibsen is teaching history at the school where Eric's father works. When he was younger he traveled the world and he knows many legends and stories. Karl and Tecla are keeping terrifying secret: Tecla can create a monstrous shadow, called Ragorlang.
The Ragorlang is a creature that can devour the energy from humans and transfer it to the body of its creator. Tecla used the creature to devour the energy of the young students that are learning in the Open Hill's school, and Karl helped her to get her hands on them by tricking them to follow him. When Hay Lin came to Open Hill, she met Karl and Tecla Ibsen in Eric's house. Karl told her the legend about the Ragorlang, and in the same evening she gets attacked by a Ragorlang, but the other Guardians saved her. Next week Will and Hay Lin are again in Open Hill, and this time Karl tricks Hay Lin and brings her to his wife. Then Tecla realizes that Hay Lin is not an ordinary girl, because of her energy, which makes Tecla years younger. She plans to steal all of Hay Lin's energy, but gets defeated by the Guardians.
However, Tecla was left weak, but not defeated, she and Karl moved to Heatherfield in order to eliminate the Guardians. She first try to turn Hay Lin in a Ragorlang, but her plan was foiled because of the intervention of Dr. folkner, a Ragorlang hunter that is after her. She then attacks a nomadic tribe of magic people who are settled down in an island on Earth and kidnapp a young girl with mental power, Erin, and sends her after the Guardians, saying her that they are the ones who sent the Ragorlangs after their people. Tecla's plan fails again because the W.I.T.C.H. manage to show Erin that Tecla was the real culprit. She and her brother help the girls before leaving to another world.
Tecla was left very weak, but she manage to restore her power and become more powerful than ever by absorbing a part of Kandrakar's magic that flows into Earth by accident. She becomes more younger, creates Ragorlangs with the power of elements and send them against the Guardians, but they defeated them, recover the stolen magic and Dr. Folkner strips Tecla of her Ragorlang, but he unexpectly decides to fuse himself with all the Ragorlang he captured over the years, becoming a threat bigger than Tecla.
Tecla doesn't give up, however, she returns to Heatherfield, knowing that the Ragorlangs were atracted by the energy of the young people that assist to Karmilla's concert. She infiltrates into Folkner's house to get her Ragorlang back, but when Folkner (now a big ugly Ragorlang-like creature) threatens all the city and takes Karl's energy when she arrives to save his wife, Tecla understand she was wrong to using a evil power to get her young back, she already lived her life, and now all what she really needs is her husband's love. She redeems herself by revealing the Ragorlang's weakness to light to the girls, who combined their power along with Folkner's trap box, trapping Folkner and the Ragorlangs forever inside it. And the end, Tecla and Karl are offered by the Oracle to stay in Kandrakar, and both accepted.