Sasha Nein is one of the main characters of Psychonauts, and one of the guest instructors at Whispering Rock Summer Camp. He sees potential in Raz, and sees him as a young version of himself. He takes Raz to his lab for training and tests, and shows a great interest in his development as a psychic.
Sasha is a top Psychonaut, who is rather famous among young and aspiring psychics. He seems to be too busy to notice this, however, as he is always in his lab doing tests and expanding his knowledge. Sasha ran away from home to become a psychonaut after he read his father's mind to see what his deceased mother was like (as his father would not tell him). He saw that his father believed his mother was a good woman and was undoubtedly an angel in heaven, but was deeply disturbed when he delved too deep and saw his mother as a sexual figure in his father's mind.
Sasha is a powerful psychic, and trains Raz in the skill of psi-blasting, and helps him to get training in several other skills.