Alexios 'Alex' Katakrinō, known to the world as an immortal god, has lived for 2,394 years, far surpassing the age of the Mikaelsons. His long life has seen him fight in the Peloponnesian War, the Crusades, and World War II, each conflict adding layers to his already complex character. Alex's appearance is striking, with sea green eyes that seem to hold the depth of the ocean and a long, brown Ivy League haircut that frames his square-shaped face. Standing at 6 feet, his lean muscle and strong, defined build are testament to his prowess in gymnastics and combat. He wields a celestial bronze Kopis sword, a gift from his half-brother Percy Jackson, and a silver and black trident that transforms into a necklace, a memento from his father, Poseidon, given when he was 12. His attire varies from slim-fit jeans and t-shirts with sneakers to cardigans or different jackets, and for formal occasions, he opts for a shirt and tie, formal trousers, jacket, and chukka boots.

Despite his divine heritage as a demigod son of Poseidon, Alex's life is not without its challenges. He struggles with dyslexia but can understand and speak ancient Greek fluently. His powers, including Hydrokinesis, Hydrogenesis, earthquake control, and the creation of storms, are both a blessing and a curse, drawing him into conflicts he seeks to resolve. Alex's personality is a blend of good-heartedness and loyalty, tempered with a tough, no-nonsense attitude towards bullies. His compassion and empathy shine through in his relationships with Elena, Caroline, Stefan, Damon, and Bonnie, making him a cherished ally and friend.

Alex's journey is one of seeking peace in a world that constantly pulls him into its battles. His deep connection with his half-brother Percy, who adores him as much as he adores Percy, provides him with a sense of family and belonging. Yet, the weight of his immortality and the responsibilities it brings often clash with his desire for a simpler life, leading to internal and external conflicts that shape his path.

In the world of The Vampire Diaries and Percy Jackson, Alexios 'Alex' Katakrinō navigates the complexities of his existence, striving to protect those he loves while grappling with the eternal nature of his life. His story is one of resilience, love, and the relentless pursuit of a balance between his divine duties and his human desires.