|No one can have everything. Nobody is being born a sorcerer. And none should be born as one! After all, all the students should decide for themselves whether they want to be sorceresses or mothers. I demand all the students to be sterilized. No exceptions.|
|- Tissaia de Vries, The Poisoned Source|
She had dark, smoothly combed hair, shining eyes and thin lips, often dressing in a camaca cape trimmed with dormouse fur thrown over her shoulder. She was also one of the oldest sorceresses alive during the Northern Wars, but appeared young due to magical elixirs.
While teaching at Aretuza, she was the one who took the young Yennefer of Vengerberg under her wing. While training her, it was Tissaia who fixed Yennefer's hunchback and cured her of her various afflictions.
In 1267, she met with Artaud Terranova, Vilgefortz and Lydia van Bredevoort, and discussed the northern kings meeting at Hagge, including the political implications the event held, such as possible plans of a second war. After being asked for his opinion, Vilgefortz ordered the council stand back and let events unfold, as reacting too promptly to false news could be devastating. While Artaud implied Vilgefortz's word was not law, Tissaia knew he held the power and command in the Brotherhood. Vilgefortz instructed them to send word to the Masters of the Third Degree, the mages on king's councils around the north, and hold a meeting to discuss plans. Tissaia also sent a letter to Yennefer directly, as she was not contactable via telepathy.
At the end of June, after several students escaped the academy to the main city, she was escorted back to Gors Velen by Rayla, and then her and Margarita Laux-Antille rented a room at The Silver Heron to look for them. One afternoon, she detected Ciri and Fabio Sachs on the run from an angry crowd, through the magical interference set off by Ciri's amulet. Believing her a novice of Aretuza, she scolded her for leaving the school, using the amulet, and spending time with a boy, putting a paralysis spell on the young girl. After Fabio revealed who she was, the two mages took Ciri to Giancardi Bank where Yennefer was able to confirm the young girls identity, and then all four went back to The Silver Heron to bath in the cellar bathhouse for several hours until Ciri fled.
During the coup, it was she who teleported a heavily wounded Geralt and Triss away from the hands of the approaching Redanian army. Shortly after that, Tissaia committed suicide slitting her wrists. Together with the other losses, her death spelled the end of the Council, making way for the Lodge of Sorceresses.
- De Vries is a common Dutch surname meaning "the Frisian".
- Vries can also mean "freeze".
- In Andrzej Sapkowski's Dynastic Descriptions, it's mentioned that a young Ilona Laux-Antille was Tissaia's assistant at one point.
- In The Witcher, there's a potion called De Vries' Extract.
- In the first game, there's an in-game book, Sorceresses and Sorcerers, that mentions her.
- In The Witcher 2: Assassins of Kings, she's mentioned by Geralt as a co-author of the compendium Masters of Magic on Curses – Selected Writings, with Margarita Laux-Antille.