return and unable to Iris-message any of his friends, Percy manages to contact Tyson through a dream. Percy instructs his brother to find Ella the harpy and to meet him near the Caldecott Tunnel. After his quest, Percy summons his hellhound Mrs. O'Leary at the tunnel and she arrives with Tyson and Ella, leading to an overjoyed Percy and Tyson reuniting. Ella comments on Tyson's bravery and Percy notices that his brother is blushing, causing Percy to tease him about the romance blooming between Tyson and Ella. Tyson takes part in the Battle of New Rome, effortlessly killing the Cyclops Ma Gasket and her children and also battling Earthborn spirits with the help of advice on their weak spots from Ella. After the battle, Tyson is present when Percy is made praetor of the legion and when the Roman Senate discusses the approach of the Greek demigods. In The Mark of Athena, Tyson is still present when the Argo II arrives. After Ella issues a prophecy, Percy discreetly orders Tyson to take Ella away, not wanting Octavian to learn of the harpy's knowledge of the lost Sibylline Books. After things go south, Percy contacts Tyson and orders him to take Ella to Camp Half-Blood where the harpy will be safe. In The Blood of Olympus, Tyson is mentioned to have brought in a few friendly Cyclopes to aid in Camp Half-Blood's defense. When Reyna, Nico and Coach Hedge are cornered by Michael Kahale, Leila and Dakota on a yacht near Camp Half-Blood, Tyson unexpectedly arrives to help with Ella, who is now his girlfriend, and Rainbow, using his ability to mimic voices to mimic Octavian and trick the Romans into disarming themselves. Taking advantage of the surprise, Tyson effortlessly knocks Kahale unconscious with a single blow to the head, which is notable because Kahale is said to be so strong that it takes someone with an immense strength to overpower him. Tyson brings Ella and Coach Hedge back to Camp Half-Blood on Rainbow and relays Reyna's message about her intention to come at sunrise. During the ultimate battle with Gaea, Tyson leads the friendly Cyclopes against the Earth goddess and her monster army. Afterwards, with the powers of prophecy no longer working, Tyson joins Ella and Rachel Elizabeth Dare in traveling to New Rome in the hopes of reconstructing the Sibylline Books, the only source of prophecies left at the