Tyson is the son of the Greek god of the sea Poseidon and a nature spirit. He is a young cyclops who tries to be "the best little brother possible" and "make his family proud." He meets Percy at Meriwether College Prep school; Tyson is the subject of a program at the school which seeks to take in a homeless kid and help him while also taking in some information about him. The Mist obscures everybody's view of Tyson's one eye, making most think he has two eyes . Tyson has severe scars on his back that were caused by a sphinx in the substation where he used to live. Tyson finds Annabeth Chase pretty. He uses his bare strength and metalworking ability to his avail in many situations. For example, while fighting different monsters in "The Sea of Monsters", his immunity to fire protected him from magical flaming spheres that would have killed anbody else that stepped in it's path of fire. During his first summer at Camp-Half Blood, Tyson makes Percy a shield with depictions of all their adventures engraved on it; it retracts into a watch when not deployed.