|“||You are not dead! I like it when you are not dead!||”|
Tyson is a Cyclops, a son of Poseidon and a nymph, and the paternal half-brother of Percy Jackson. He is currently transcribing the Sibylline books with Ella the harpy. Tyson is the boyfriend of Ella.
Tyson was born from Poseidon, the god of the seas, earthquakes, and the father of horses, and an unknown nymph. He was one of the many homeless cyclopes that lived between the alleys in New York City.
Tyson spent the first seven years of his life living in a large cardboard box. While living on the streets, he was attacked by the monsters who were brave enough to attack him. This resulted in many scars on his body, but mostly on his back. One of the monsters that attacked him was the Sphinx. Tired of these attacks, Tyson prayed to his father for help sometimes.
Eventually, Tyson's prayers were answered as people from Meriwether College Prep found him living out of a refrigerator box. They took him in as a type of class project, where students would learn about homeless children and record their changes. While the school did take care of him during school hours, he still had to fend for himself outside of school. He eventually met and befriended Percy Jackson, his half-brother. Percy's mother, Sally, felt the school wasn't doing enough for Tyson and would call social services to help, but they never found him in the alley where he lived.
While at school, it didn't take long for the other kids to notice that Tyson wasn't a fighter and he would be picked on by the other students. Percy was the only one that defended him, which resulted in his own isolation from the other students. Percy was Tyson's only friend.
|“||He's more like a half-brother on the monstrous side of the family. Like... a half-brother twice removed or something.||”|
– Percy, denying his relationship with Tyson
Later during gym class, Tyson asked Percy to watch over him and block him from others' views while he changed into his gym clothes because the other kids would sometimes pick on him since he had terrible scars on his back. Percy never asked about the scars since he lacked courage. Once they entered the gym, Matt Sloan made himself and Percy team captains but picked all the bigger and stronger kids for his team (including several giants disguised as children from Detroit) while Tyson ended up on Percy's. Other team members were Corey Bailer, a computer geek; Raj Mandali, the calculus whiz; and six others with unknown names. Tyson noticed quickly that the three new kids on Matt's side, Marrow Sucker, Skull Eater, and Joe Bob smelled funny.
It is quickly revealed that the three new students were actually Laistrygonian Giants, who started attacking the gym with flaming dodgeballs. Just as Percy was about to be hit, Tyson stood in front of him and caught the two dodgeballs heading in his direction, which was when Percy discovered that he was immune to fire. He then sent them back at Marrow Sucker and Skull Eater, who was quickly turned to dust. Joe Bob later managed to hit Tyson, sending him sliding against the back wall of the gym. Percy took the giant's attention away from Tyson but was almost killed before Annabeth attacked the monster from behind, taking off her invisibility cap.
Annabeth told Percy and Tyson to follow her outside, as she knows they would be blamed for the destruction of the gym. Tyson called Annabeth pretty, which she reacts to with revulsion. Annabeth called on the Gray Sisters' Taxi, but they refused to take Tyson until Annabeth promised extra pay. During the entire ride to Camp Half-Blood, Tyson felt incredibly car sick and almost threw up.
Once arriving on Half-Blood Hill, Percy noticed that Clarisse La Rue was defending the camp from Colchis Bulls, which had managed to break into the camp's magical borders because of Thalia's pine tree wasn't functioning properly. Percy sprung into action, but he told Tyson to stay behind out of fear of him being hurt. However, Percy is quickly put in danger and almost burned alive, when Annabeth told Tyson to save Percy and giving him permission to enter the camp. Tyson stepped in between Percy and the bull, taking the blast of fire. However, he remained unharmed and smashed the head of one bull with his fists. It was then that Annabeth noticed that Percy did not know what Tyson really was. She told him to look at Tyson closely, which Percy did and saw that he only had one eye, meaning he was a Cyclops.
Tyson is then introduced to Chiron, who was fired after the poisoning of Thalia's Tree. Tyson called Chiron a pony, which he took mild offense to and had to repeatedly tell the young Cyclops that he was a centaur. Then, during dinner, Tyson is forced to sit at the head table with the new camp director, Tantalus. When trying to find a place to place the monster, a hologram of a trident appeared above his head, meaning Poseidon had claimed him. Percy then made the connection that Tyson was his half-brother.
Percy did not take this well, feeling that he went from a real hero at camp to the laughing stock of the camp. Other campers started to bully him and he did not take this well. He would even try and distance himself from Tyson and say he was like a distant relative whenever Tyson was not around. This eventually led to a fight with Annabeth while building a chariot, resulting in Percy and Annabeth building separate chariots instead of one like they had planned. Tyson used his knowledge of forging, which he had learned from Charles Beckendorf, to help Percy make the chariot while Percy calmed the horses. During the actual race, Tyson was Percy's protector, using a large club to scare away any other drivers who got to close, but his large weight slowed it down. They eventually lost the race, thanks to an attack by Stymphalian Birds.
That night, Hermes made Tyson think that Percy was calling for help, but it was only a trick to lure him to Percy so that he, Annabeth, and Percy could get on the Princess Andromeda. Poseidon helped by sending them a pod of Hippocampus and Tyson named his Rainbow. They climbed on board and found rooms to sleep in overnight. Once waking and finding that the ship had monsters on board, they tried to escape but heard Luke Castellan talking to someone. Tyson used his abilities to mimic what he heard, but this upsets Annabeth greatly. However, Luke quickly caught on to them and sent Agrius and Oreius to capture them, who together were able to hold off Tyson. However, they managed to escape the ship when they separated the bear twins and Tyson fought them off before sailing off in a lifeboat with Percy and Annabeth. While hiding from Luke and the coast guard in the James River Safehouse, Percy asked Tyson to look for donuts in the wilderness so he could talk to Annabeth alone. Tyson went outside and found a Monster Doughnut shop. Annabeth recognized this as a sign of a hydra being born, and it soon appeared and attacked them. Tyson managed to hold it off for a while but even he was soon overwhelmed. They are only saved when Clarisse La Rue appeared in the CSS Birmingham to kill the hydra with fire.
Tyson was invited on board with the others as they sailed toward the Sea of Monsters. While passing by one of the entrances past Charybdis and Scylla, then engines started to overheat and Tyson went down to give the ship more power. Being immune to heat, he managed to give the ship more power while holding it together long enough for the ship to get through before it exploded which presumably killed Tyson though it is later revealed he managed to survive. When Annabeth and Percy land on an island, Annabeth explained that Tyson could have survived, but it was half-hearted and Percy felt great guilt about the way he had treated Tyson.
Tyson, however, managed to survive the explosion and Rainbow saved him. The two then followed Percy all around the Sea of Monsters until they arrived on Polyphemus' island. He then tossed a rock, which landed in Polyphemus' throat, causing him to choke while he was about to crush Percy. Being a Cyclops, Polyphemus' Sheep did not attack Tyson while he went to grab the Golden Fleece but became restless as he led them away from the others so they could get to the Queen Anne's Revenge.
Polyphemus returned and called Tyson a traitor to his kind. Tyson said he was not and Polyphemus was not his kind. He then helped Percy fight the Cyclops by swatting away boulders and fending him off. Tyson eventually pushed Polyphemus onto the beach before swimming for the ship. However, because Clarisse kept insulting Polyphemus, he managed to sink the ship with a rock, but the Hippocampi arrived to bring them back to Florida.
Once they all noticed that Thalia's Tree would be dead soon as time passed differently in the Sea of Monsters, Tyson pulled out the money in his bag and gave it to Clarisse to fly back to camp alone, as it said in the prophecy. A moment later, Luke attacked the group with Agrius trying to attack Tyson, but Tyson pushed him aside. Luke then told Percy to call Tyson off or Oreius would bash Annabeth and Grover and eat them. Tyson stopped fighting but was carried off when the Party Ponies ambushed Luke's army and took them to their own camp before taking them to Camp Half-Blood.
Once back at Camp Half-Blood, Tyson helped Percy and Annabeth on their chariots for the next race and gave Percy a Wristwatch Shield to protect himself from the other racers. After returning the Golden Fleece to camp, the other demigods treated Tyson like a hero and Percy dedicated his win in the race to Tyson. Tyson later said his goodbyes to Percy, as he had been offered an internship at the Underwater Forges of the Cyclopes. With the war coming, Poseidon needed him to help make weapons for the Olympians. Tyson walked to the beach and headed down below the ocean on Rainbow.
Tyson only appeared briefly because he was in the Underwater Forges Of The Cyclopes. Percy had sent Tyson an Iris Message to see how things were going in the forges. However, when he asked how Annabeth was, Percy did not tell him she had been captured. He attempted to hug Percy through an Iris Message, but it did not work. Later, Percy sent Tyson another Iris Message and he told Percy that he was coming to camp the next summer.
|“||"Now we can eat peanut butter sandwiches and ride fish ponies. We can fight monsters and see Annabeth and make things go BOOM!"||”|
–Tyson after meeting Percy again
Annabeth leads the quest into the Labyrinth and is very excited since this is her first time leading one. She broke the rule of only two companions on a quest, by choosing Percy, Grover, and Tyson. She descends into the Labyrinth with Percy, Grover, and Tyson to find a way to stop Kronos' evil forces from entering the borders of Camp Half-Blood by searching for its inventor, Daedalus.
As they go into the Labyrinth, they face many dangers. Tyson finds and frees his idol, Briares the Hundred-Handed One, but is disappointed to find out he is afraid of Kampê and refuses to fight. They split up and Tyson follows Grover, who goes a different direction in search of Pan. They all reunite and flee the Labyrinth after the help of Rachel Elizabeth Dare and Daedalus.
The fight begins the Camp is in danger and all seems lost until Briares and Daedalus arrive with Mrs. O'Leary to help fight. During the battle, Tyson defeats and several Earthborn giants. At the end of the book, Grover unleashes the cry of Panic, greatly disrupting — but not ending — the battle.
Tyson meets with Percy again when he wakes up in Poseidon's palace after the explosion of the Princess Andromeda. Tyson finds Percy in the water and consoles him when Percy learns about Beckendorf. He seems to want to fight in the battle and is sad because he has to work in the armory. When Percy leaves he states "Good-bye brother don't let monsters kill you dead!"
When Tyson and a few other Cyclopes are having lunch, the armory wall explodes and a dozen Cyclopes are blown in. Before he can help them, they turn to silt. He grabs a club from a fallen Cyclops and charges, saying an unintelligible phrase, as he has peanut butter in his mouth. He was supposed to say, "For Poseidon!" but he said "PE-TAH-BUH" instead. The other Cyclopes in the armory used the war cry, "PEANUT BUTTER!". Poseidon states that it is a "strange battle cry". After this event, Poseidon comments that Tyson is a good fighter and lets him lead the army of Cyclopes that helped defeat Typhon, the gods' greatest enemy.
On Olympus, Tyson is promoted to general of the Cyclops army, and given a new club, which he calls "Stick!"
Rainbow the Hippocampus asks for Tyson when he comes to take Percy to camp. Later, Annabeth brings Percy a birthday cupcake with blue frosting which Tyson helped her to bake. According to Percy, it looks "like a brick with extra blue cement".
Tyson does not make an appearance but is mentioned by Annabeth to be looking for Percy as well as Nico and The Hunters of Artemis.
Tyson is searching for Percy along with Mrs. O'Leary. He appears twice in Percy's dreams, once when he is searching and wonders why Percy's scent is getting farther away and the next when Percy tells Tyson to find Ella and go to Camp Jupiter to wait for him. When Percy returns, he whistles for Mrs. O'Leary, and the three appear. During the reunion, Tyson and Ella show some affection for each other and Tyson tells Percy that she is really pretty; upon learning that Frank Zhang is a very distant descendant of Poseidon Tyson proudly proclaims him as his brother, just like with Percy. Tyson then agrees to join the fight and puts on a Camp Jupiter banner so that the Romans will not consider him an enemy like the rest of the evil Cyclopes. He even manages to knock out Ma Gasket, who is confused by the Greek Cyclops. Tyson offers to help Percy fight Polybotes, but Percy claims he will be fine. Tyson is later seen celebrating the victory in the mess hall with Ella and consuming peanut butter sandwiches at an alarming rate. The next day during the Senate meeting, Tyson sees the Argo II coming and goes out to meet it.
Tyson is recognized by Annabeth as a familiar face along with Mrs. O'Leary, something she is happy about. Tyson waves at her enthusiastically and Annabeth deduces that he and the hellhound are in good spirits. Later, while Percy, Annabeth, Jason Grace, Piper McLean, Leo Valdez, Hazel Levesque, Frank Zhang, Reyna Avila Ramírez-Arellano, and Octavian discuss the Prophecy of Seven, Tyson, followed by Ella and Mrs. O'Leary, interrupts their meeting to inform Percy that Ella did not want to go on the Argo II. Annabeth, once again, is happy to see them as they warm her heart calling Tyson family. Ella spots the demigod and recites a prophecy much to Octavian's amazement. Annabeth quickly dismisses the idea and tells Tyson to take Ella and Mrs. O'Leary someplace else. Reyna agrees and the Cyclops shadow-travels away. On the Argo II, following the attack on New Rome, Percy tells his companions that he sent Tyson an Iris-message, telling him to head to Camp Half-Blood. When they reach the Atlantic Ocean, Chiron tells Annabeth and Piper through a dream vision that Tyson, Ella, and Mrs. O'Leary had arrived safely, and, if necessary, Tyson could summon the Cyclops army to the camp's defense.
Grover mentions that Tyson is dating Ella during the meeting with the Romans.
When Camp Half-Blood detects the arrival of Reyna, Nico, and Coach Hedge nearby, they send Tyson and Ella to greet them. The two travel on Tyson's old friend Rainbow. Tyson is able to trick Michael Kahale with Octavian's voice and subdue him. After exchanging news, Reyna has Tyson and Ella take Coach Hedge back to camp on Rainbow. Tyson later fights in the final battle.
After its over, Tyson promises to help reconstruct the Sibylline Books which Ella has memorized.
Tyson answers the door and invites Apollo and Frank Zhang into the bookstore. He takes them to the back room where Ella is tattooing the passages of the Sibylline Books that she red onto his back. He finds the process enjoyable.
During the next day’s senate meeting he shows the senators his tattoo, disturbing some of them in the process as Ella reads the prophecy.
During the battle, Apollo meets up with him and Ella outside the Temple of Jupiter Optimus Maximus. He pets Arion on the snout before the horse runs to New Rome to help. When Apollo chooses to summon his sister, they head to the Temple of Diana. As Apollo performs the ritual Tyson dances and lets the mortal god read what to say off of his left armpit. However, nothing happens as Ella reveals Apollo messed up a line. Apollo then heads into battle while he and Ella stay behind.
A few days later after the battle, Apollo and Meg meet up with him and Ella at the bookstore to say goodbye and revive a prophecy.
|“||I couldn't help smiling, he was so enthusiastic about everything.||”|
In spite of his naiveté and seeming density, Tyson is smarter than he seems and very determined. In The Battle of the Labyrinth, he has matured, though he still retains his innocence. He noticed the real reason why Percy cannot tell anyone about Nico being the son of Hades. Tyson's earnest attitude reminds Briares who he really is and decides to help Camp Half-Blood as a result.
Tyson cares a great deal about his friends and is willing to risk his life for them if necessary. He shows a strong love for pegasi and hippocampi (which he calls "chicken ponies" and "fish ponies" respectively), though the former are nervous around him. In order to protect himself and his friends, Tyson began to take on the stance of a leader in The Last Olympian and becomes less of a child in Poseidon's eyes as well.
Tyson is terrified of Grover because the "itchy goat fur" makes him sneeze, but as he got over it to maintain their friendship it is possible that he has gotten over his fear of Satyrs completely. When he rescues Reyna, Nico and Coach Hedge, he comments on Coach Hedge's "itchy goat fur" but displays no fear of him and even helps him back to camp, indicating that he has overcome his fear of satyrs completely.
Furthermore, Tyson is very much terrified of everything related to death, such as the skeleton warriors aboard Clarisse's ship and initially Nico.
Tyson is two meters tall (though he can grow up to 30 feet tall at will), and very broad-shouldered. He has very messy brown hair and one large brown eye, but he appears to have two because of the Mist in the mortal world and in Poseidon's forges. He is known for not brushing his teeth.
While he has the ability to grow to a giant height at will, in the Blood of Olympus, its indicated that Tyson's usual height hasn't grown much or at all as he's commented on being small and young. He has scars on his back caused when the Sphinx attacked him for being unable to answer its riddle.
In The Tyrant’s Tomb, Tyson is being used to write down the prophecies from the Sibylline Books, having many of them tattooed onto his back and chest with an index on his thigh and the incantation to summon a god on his left armpit. In addition, he has a tattoo of Rainbow on one of his kidneys.
Tyson possesses several abilities typical of Cyclopes and children of Poseidon:
- Massive Strength: Though he is still young, Tyson is immensely strong, even among other Cyclopes. In The Sea of Monsters, he managed to beat also two bronze bulls the size of elephants with his bare hands, was able to hold his own against a Hydra and managed to tackle Polyphemus who was almost twice as big as him to the ground easily so that he and Percy could escape. When he almost punched Luke, Percy stated that Tyson could punch with enough force put a hole in titanium. In The Battle of the Labyrinth Tyson freed Briares by ripping the door off its hinges with his bare hands "as if it was made of wet clay", and effortlessly pounded Earthborn giants into mounds of clay. The most extreme example of his strength was in The Son of Neptune when Tyson managed to kill the larger Ma Gasket (a female Cyclopes that also has very enhanced strength for her species) with only two mighty punches.
- Superhuman Durability: As a Cyclops, Tyson is able to withstand many physical blows and damage. He could survive Kampê's poison, though it was still quite painful to him.
- Superhuman Reflexes: Despite his occasional clumsiness, Tyson has fast reflexes. In The Sea of Monsters, he managed to catch two flaming cannonballs flying at alarming rates.
- Vocal Mimicry: Like most other Cyclopes, Tyson can imitate voices. In The Sea of Monsters, he imitates Luke and Chris Rodriguez. In The Battle of the Labyrinth, he imitates Briares and Kampê.
- Superhuman hearing: He possesses sharp hearing.
- Height Manipulation: As a Cyclopd, Tyson can grow up to 30 feet tall at will.
- Fire Immunity: As a Cyclops, Tyson is immune to fire and extreme heat, with the exception of the Flames of the River Phlegethon. He manages to survive a blast from the Colchis Bulls, whose fire were too hot even for Percy to withstand.
- Underwater Breathing:: As a Cyclopd, Tyson can breathe underwater. This is first shown in The Last Olympian.
- Forging skills: As a Cyclops, Tyson possesses innate talent with metal works and is gifted with extra delicate hands, which allows him to make small items with remarkable precision and detail. He built the chariot for his cabin and many weapons in forges. He designed special javelins and an extremely durable complex wristwatch/shield, which he later repaired as well. Tyson's skills impressed Charles Beckendorf and even Briares after a year of practice in The Battle of the Labyrinth.
- Tongue of the Old Times fluency: According to Tyson in The Battle of the Labyrinth, this is the ancient language that Gaea spoke to the Titans, Elder Cyclops, and Hekatonkheires before the birth of the Olympian gods. Tyson can understand it perfectly and translate it.
- Empathy (possibly): In The Sea of Monsters, during a talk, he was having with Percy, Tyson seemed to know exactly what his brother was feeling. Because of this, Percy wondered if Cyclopes could read emotions as satyrs could.
Tyson and Ella meet at the end of The Son of Neptune. He takes a liking to her and blushes whenever she is mentioned. Tyson states that Ella is pretty and seems to spend a lot of time with her. In The House of Hades, Grover states that Ella and Tyson are dating. She comes with Tyson to help in The Blood of Olympus.
Tyson meets Rainbow the hippocampus when he, Percy, and Annabeth embark for the cruise ship the Princess Andromeda. Tyson is upset that Rainbow (the name he gave the sea creature) cannot follow them on board, but is convinced they will see each other again. Rainbow followed Tyson all the way to the Sea of Monsters and rescued him when the CSS Birmingham exploded. Tyson and Rainbow then went looking for Annabeth and Percy, eventually finding their way to Polyphemus' Island. When Tyson called him for help, Rainbow came immediately with friends to carry Percy, Tyson, Grover, Clarisse and Annabeth to safety. Rainbow later reappeared to carry Tyson to the underwater Cyclops forges.
After The Sea of Monsters, Tyson and Rainbow meet at various instances throughout the course of the Percy Jackson and the Olympians series. Most notably, he is able to get Rainbow to carry him and Ella to a yacht where Reyna, Nico di Angelo and Coach Hedge were. Rainbow is shown have stayed close with Tyson, probably due to his time living in Atlantis.
Tyson knows Grover through Percy, but they didn't feel comfortable around each other, due to Grover being scared of Cyclopes and Tyson sneezing from Grover's hair. However, while in the Labyrinth, Tyson goes with Grover to help protect him while they search for the lost god Pan. After this quest, the two seem to be on better terms with each other.
Tyson became infatuated with Annabeth the first time they met. While he thinks Annabeth is pretty and is very protective of her, she initially treated him harshly because she had a prejudice against all Cyclopes mainly because a Cyclopes had once captured her and nearly killed her friends. However, after Tyson supposedly sacrificed himself to save the crew of the CSS Birmingham, Annabeth feels bad for the way she had treated him up until that point and admits he is not like other Cyclopes. When they are reunited, she is much kinder to him.
During The Titan's Curse, after Annabeth is kidnapped and Percy calls Tyson while he is working in the underwater forges and Tyson asks how Annabeth is. Percy had to lie to Tyson and told him she was fine. Once Tyson learns the truth, he is overjoyed that Annabeth was rescued safely. Annabeth trusts Tyson enough to bring him with her to the Labyrinth, even if it broke the sacred rule of only three people per quest. He was happy to spend time with her at the Labyrinth.
Mrs. O'Leary and Tyson get along very well, as Tyson is the only person that Mrs. O'Leary can play with without worrying about injuring him.
During The Son of Neptune, the two of them teamed up in order to find Percy, who at the time was missing. This shows their bond with another has helped them in hard times.
When Tyson was first allowed at Camp Half-Blood, Beckendorf was one of the first demigods to actually accept Tyson. Beckendorf's father, Hephaestus, uses Cyclopes in his forges and Beckendorf offered to teach Tyson how to become a blacksmith at the camp's forges.
When Percy wakes up in Atlantic after destroying the Princess Andromeda, he sadly informs his half-brother of the son of Hephaestus’ demise, showing his respect for the fallen half-blood.
While growing up on the streets, Tyson would pray to Poseidon for help and a friend. After Tyson arrives at Camp Half-Blood, Poseidon claims Tyson as his son, which earns him a lot of ridicule but excites him as it brings him and Percy together. Tyson later tells Percy that he believed Poseidon failed him, but then answered his prayer by sending him a brother.
Poseidon later visits Tyson in his dreams and invites him to work in the Cyclops forges, an offer which he takes. Poseidon becomes protective of Tyson, much to his dismay. While Tyson wants to help his father fight Oceanus in The Last Olympian, Poseidon keeps him in the forges to make weapons. However, Poseidon eventually allows Tyson to help in the fight against Typhon and even leads the charge.
Percy and Tyson knew each other before they knew they were related as they went to the same school. Percy would try and protect him from bullies, but would never look at Tyson directly. Unknown to Percy, Tyson's presence had been shielding him from monsters all year. When Laistrygonian Giants attack, Tyson protects Percy selflessly. After they found out they were related, Percy felt a bit ashamed of his new brother and wondered how they could be related. It wasn't until the ship they were on exploded that Percy began to think of Tyson as a brother, thinking he had sacrificed himself to save him and Annabeth. When they are reunited, Percy is happy. At one point, Tyson tells Percy that after his hard life on the streets, he prayed to Poseidon for a friend and Poseidon sent him a brother which he is very happy about.
Over the rest of the series, Percy treats Tyson like a real brother and has come to accept him, even his crushing bear hugs. Even when apart, the two remain in touch. Tyson is always happy to spend time with his brother and help him in whatever way he can, like fixing his weapons and protecting him in battle. After Percy went missing in Lost Hero, Tyson searched for his brothers for months and cried when he finally found him.
Tyson is portrayed by Douglas Smith.
The film depiction of Tyson differs greatly from the books. He appears to be more intelligent and more articulate but is still incredibly clumsy. He also prefers to hide his status as a Cyclops by wearing sunglasses. He admits that he is afraid that he is the monster he is seen as, due to an incident where he smiled after scaring a group of Boy Scouts. In spite of feeling like an outcast because of what he is, he maintains a youthful outlook on life, having faith in his father and taking joy in the wild ride of the Chariot of Damnation. He also looks up to Percy and willingly puts himself in danger for him, believing Percy would do the same for him. It is also shown in the film that Tyson is able to heal himself with water like Percy.
His past is not explored in great detail, but he reveals that when he was living in the mountains, he accidentally scared a group of Boy Scouts. He arrives in Camp Half-Blood on his own, having been guided there by a glowing trident. He enters the camp due to its weakening defensive barrier. He presents himself first at the Big House to Mr. D and Chiron, who in turn informed Percy. Shortly after being teased by Clarrise, Tyson helps save her from a Colchis Bull due to his great strength and resistance to fire.
After Percy, Grover and Annabeth decide to go on the quest for the Golden Fleece, Tyson sneaks after them, making a great deal of noise due to his full pack. In spite of Annabeth's misgivings about having a cyclops on the quest, Grover is eager to have him accompany them after hearing from Tyson that the fleece is guarded by Polyphemus. Exasperated by Tyson's conspicuousness, Annabeth sprays him with a bottle of the Mist to hide his single eye.After finding the location of Luke's ship, the Princess Andromeda, Tyson asks his father for help getting there and is rewarded with the arrival of a hippocampus. On the ship, they are quickly captured, and Annabeth believes that Tyson intentionally had them captured by making noise. They manage to escape from the ship in a life-raft, but Tyson's Mist-induced disguise wears off, returning him to his normal cyclopean appearance, which reminds him of his past of rejection. In an effort to cheer him up, Percy offers to let him steer the ship with the thermos of the four winds, which he accidentally drops into the Sea of Monsters.
On the island of Polyphemus, Tyson tried to reason with the giant cyclops but fails, since Polyphemus sees him as a traitor to their kid for siding with demigods. After trapping Polyphemus in his cave, Tyson takes a crossbow bolt meant for Percy, falling from a ledge into an underground stream. He later returns to save Percy from Luke, revealing that the water had healed him. He returns with the other demigods and is told by Percy that he does not need to hide who he is anymore.
"Tyson" is an Old French name meaning "high spirited" which could pretty much sum up his behavior as Tyson is very high spirited and childlike
- Tyson shares his name with professional boxer Mike Tyson.
- He is tidier than Percy, as see in The Battle of the Labyrinth where he was cleaning up Poseidon's Cabin's mess. In The Last Olympian, Percy said he didn't have Tyson cleaning after him when he and Annabeth were inspecting the Cabins.
- His favorite food is Peanut butter.
- He idolizes Briares, who is his brother-in-law through Kymopoleia.
- As shown with his relationship with Frank Zhang, Tyson considers all descendants of Poseidon to be his siblings, even if they are technically his nieces or nephews.