Leo Valdez is a fictional character from the Percy Jackson series and its sequel series, The Heroes of Olympus, created by author Rick Riordan. He is a demigod, the son of Hephaestus, the Greek god of fire and craftsmanship. Leo is known for his mechanical skills and ability to create and control fire, which he often uses to help his friends on their adventures. In the series, Leo is characterized by his humor and loyalty. He travels with a group of demigods, including Percy Jackson and Annabeth Chase, as they embark on quests to save the world from various mythological threats. His unique talents and inventive spirit make him a valuable member of the team.