Geralt of Rivia is a witcher and the main protagonist of the Witcher series by Andrzej Sapkowski and its adaptations, including The Witcher (PC), The Witcher 2: Assassins of Kings, and The Witcher 3: Wild Hunt video games. Like all witchers, Geralt is a monster hunter for hire. He possesses superhuman abilities and is a master swordsman. During the Trial of the Grasses, Geralt exhibited unusual tolerance for the mutagens that grant witchers their abilities. Accordingly, Geralt was subjected to further experimental mutagens which rendered his hair white and may have given him greater speed, strength, and stamina than his fellow witchers.
Geralt is also known as Gwynbleidd, meaning "White Wolf" in Elder Speech. He was given this alias by the dryads, and is also called the Butcher of Blaviken after an unfortunate incident in that town.