Sabrina Glevissig is a sorceress, as well as a member of the Brotherhood of Sorcerers.
Ascension at Aretuza
Sabrina is one of the initiates brought into Aretuza by a sorceress named Tissaia de Vries. Sabrina joins the other girls in the greenhouse, who much like herself can tap into magic. Tiassai explains the dangers of magic and how each one of them showed an aptitude for controlling it, making them conduits of chaos, though magic itself is the control of chaos. She has gathered them for a trial. Before each of them sits a flower and a stone. They are to lift the stone without touching it. Fringilla is the first initiate to lift the stone, however, as demonstrated, magic comes at a price. Only seconds after Fringilla lifts the stone does her hand rapidly age and shrivel up. There is a give and take with magic, as Tiassai demonstrates by lifting the stone, but with the flowers in hand to represent what is taken as they grow old and die. Sabrina follows her lead, as do the other initiates, with the exception of Yennefer, who is unable to move the stone.
Several weeks have passed. The initiates are taken to Tor Lara to bottle lightning. It is the most potent place on the continent, off limits to everyone except to the Brotherhood of Sorcerers. This latest trial is to test their ability to control the ultimate expression of chaos. Sabrina raises her bottle effortlessly captures the lightning. In her jealousy, Yennefer shoots lightning at Tissaia, who redirects it back into the sky.
Conclave of Northern Mages
Sabrina was one of many mages who attended the conclave of Northern mages in Aretuza. Artorius, Stregobor, and Tissaia led the conclave. Artorius and Stregobor had no desire to go to war with Nilfgaard. Especially not for Cintra, who rejected their mages for decades. Rather than watching them fall, Tissaia wanted to help Cintra defeat Nilfgaard. Sabrina, Vilgefortz, and Vanielle sided with Tissaia, wanting to convince the kings to send their armies because if they didn't stop Nilfgaard now, more kingdoms would fall.
Fringilla arrived at the conclave and denounced any suspicion that Nilfgaard was planning to take over the continent. Under their new leader, Emperor Emhyr, Nilfgaard had strengthened trade and funded research. Tissaia accused Fringilla of rejecting the order and way of life that took centuries to build. Fringilla retorted that they simply modified it. They've taken a new path, guided by the White Flame. When Triss claimed that Nilfgaard also forced mages into servitude and practice black magic, Fringilla responded that they believed in shared sacrifice and that there was no such thing as dark or light magic. Fringilla believed that in taking Cintra, they had a chance of saving the continent. The mages put it to a vote. Unfortunately, most side with Stregobor and Artorius to allow Cintra to fend for themselves.
Battle of Sodden Hill
Approximately 60 mages, Sabrina, Yennefer, Tissaia, Vilgefortz, Vanielle, Coral, and Triss included, board a ship headed for Sodden Hill. They must get to the Elven keep that guarded it before Nilfgaard did. They had already sent word to the Northern kingdoms. Temeria and Kaedwen agreed to join them in defending the land. The plan was to protect the keep. Sabrina, Yennefer, Tissaia, Vilgefortz, Vanielle, Coral, and Triss arrived at the keep. The only thing separating Nilfgaard from the North. They were greeted by a man. Yennefer advised him to take the children and hide, but as he explained, there was no more hiding from Nilfgaard. Their only chance was to fight.
The keep was attacked by Fringilla and Nilfgaard in the late hours of the night. The sun had risen and the Northern mages made it through the night. Unfortunately, Nilfgaard arrived much sooner than they anticipated and the Northern armies were still a ways out. There were only 22 of them left, Sabrina, Triss, Yennefer, Tissaia, Vilgefortz, Vanielle, Coral, and Atlan Kerk included. They witnessed as a thick fog consumed the mountains around them, signaling Nilfgaard's encroachment. Tissaia ordered Sabrina to take the villagers to the artillery room while she and Triss head down.
Sabrina led the archers from within the castle. The villagers packed blue meteorite into bottles and launched them into the sky. Sabrina and the others shot the bottles with arrows, causing massive explosions, taking out the Nilfgaard army below.
At some point during the battle, Sabrina had been taken over by a kind of silver worm-like parasite that slithered into her ear, as well as the ears of two villager boys. She handed them two bottles of explosive blue meteorites. Sabrina sneaked up behind Yennefer and stabbed her in the abdomen with an arrow. The two young boys, also under the control of the parasites, took their bottles of blue meteorite and dropped them on the tables filled with blue meteorite, causing a massive explosion on both ends of the keep that sent Yennefer and Sabrina flying off the tower, though the former managed to stick the landing. The fall appeared to return Sabrina to her normal self as she apologized for attacking Yennefer.