
He was the first witcher to survive these mutations and as a result of these experiments, he lost all pigmentations in hid body hence, the pale skin and white hair.

Due to his spectacular performance, the witchers at Kaer Morhen decided to put him through even more dangerous mutations. He survived the mutations from the Trial of the Grasses which helped him gain a high resistance to poison and disease. What made Geralt special was his unusual tolerance to mutagens. He was trained by Vesemir, the last of the masters. He’s the son of the sorceress Visenna who left him at Kaer Morhen, the training ground for witchers.

Geralt of Rivia is a witcher also known as the White Wolf because of his pale white hair and extremely impressive track record against monsters.
