He was one of the main antagonists of the Percy Jackson and the Olympians series. He was tricked by the Titan Kronos into hosting his spirit. Although he is considered as the series' main human antagonist, he died at age twenty-three as the hero of the Great Prophecy.
Percy Jackson season 1 finale reveals Luke as the friend who betrays Percy and the one who stole Zeus' Master Bolt. Luke's motivations for siding with Kronos over the Olympians stem from his resentment towards his father, Hermes, and his belief that the gods are terrible parents.
Luke showed his darker side as a villain for most of the series, so his character was mostly described as 'evil', however he was a hero in the end, so his character did bad things but was good at heart. In this way, he is more 'heroic' in the old sense of the terms, such as the stories of Theseus, Jason or Hercules.
Nothing ever happens between Annabeth and Luke, but Percy gets jealous of the other demigod. Annabeth also outwardly admits she had a crush on Luke in The Mark of Athena, the third book in Riordan's Heroes of Olympus series.
Luke Castellan's primary motivation (at least in the first book) was resent at Camp Half Blood and at his father. at the end of the first book, he has a scorpion with fatal poison attack Percy, explains his motivations and leaves.
Kronos: The Lord of the Titans and the main antagonist of the series. He tries to get Percy to join him and fight against the Olympians. His weapon is a sword named Backbiter remade into the scythe.
Upon returning to Camp Half Blood, Percy is betrayed by his friend Luke, son of Hermes, who turns out to be the human hero whom Kronos used for the theft. Luke poisons Percy, and tells him before leaving that Kronos will rise and destroy the age of the gods. Western Civilization is unraveling.
Annabeth. It's pretty clear that he loved Annabeth as far back as the first book The Lightening Thief. He described her as attractive and I think that's when he started having feelings for her. Percy didn't even like Rachel and doesn't now.
Percy pulled Annabeth close and kissed her... long enough for it to get really awkward for Piper, though she said nothing. She thought about the old rule of Aphrodite's cabin: that to be recognized as a daughter of the love goddess, you had to break someone's heart.
Luke dies in The Last Olympian when he is given Annabeth's knife by Percy. He sacrifices himself to defeat Kronos by stabbing himself under his left arm where his mortality was still kept intact after his bath in the River Styx (known as his Achilles heel).
However, it's Medusa's resentment speaking during this scene. Annabeth doesn't betray Percy in Riordan's books, and she's even more hurt by Luke's betrayal than Percy. Percy and Annabeth eventually end up together, and they spend much of the series endlessly loyal to one another.
While this may seem like a betrayal at first, it was actually Grover playing the part of protector to a tee. Knowing that monsters will find Percy at Yancy, Grover realizes he has to get him away from the school as quickly as possible.
Luke serves as a guide to Percy as he adjusts to camp life and gifts Percy with magical shoes before Percy embarks on his quest, further encouraging Percy to believe he has made a true ally and friend. Luke betrays Percy and the gods because he himself feels betrayed.
Luke Castellan: He was stronger than Percy at the Percy Jackson and the Olympians, but as Percy grew older and got more experienced, Luke would be outmatched if he was alive. Lityerses: He is an incredible swordsman, and although he lost to Jason, I imagine he will be a match to Luke.
She appears first in the first novel of the series, The Lightning Thief. In the series she becomes close friends with Percy Jackson, later becoming his main love interest and girlfriend. Annabeth is architect of Olympus and one of the leaders in Camp Half Blood for half bloods/demigods.
In fact, one of the most important characters in the series is Percy's very best friend and guardian, Grover Underwood. Grover is a satyr, a Lord of the Wild, and a Chosen of Pan.
Luke Castellan: Long before Percy Jackson won her heart, there was fellow demigod, Luke Castellan, Annabeth's childhood friend and longtime crush. But as her feelings develop for Percy, she realizes Luke was more like family to her than a true love interest.
In the demigod diaries when Thalia kissed Luke on the cheek I thought that was really cute! But they didn't get a lot of moments together on the book. I kinda ship them but not too much.
There, Thalia fights her old friend Luke, and it seems that she has strong feelings for him, and they discover that Kronos used Thalia to twist destiny into his hands, since she would be turning sixteen on the day following the Winter Solstice.
Thalia's the daughter of the strongest god, and has similar power levels to Percy. If it was a battle of who was more powerful, then Percy would win. However it's not. They are even in blade combat and Thalia is more agile and is very talented with a bow.
This is the chapter where Annabeth first kissed Percy, right before he was blasted to Calypso's island. Enjoy! I had my invisible cap on, and Percy was no where to be seen.
An altercation with Clarisse allows Percy to discover his father is Poseidon, one of the “Big Three” gods. This revelation is cut short when a hellhound attacks Percy from the Fields of Punishment.
