Lucca Ashtear's design was created by Akira Toriyama. Her design had been fairly consistent throughout development, though at one point she wore a headband instead of a cap. Her personality is described as dependable but boisterous. She is a genius scientist who creates multiple advanced technologies, including teleporting and time travel technology. Director Yoshinori Kitase was responsible for the creation of extra scenes featuring Lucca. Chrono Trigger story planner and script writer Masato Katō noted that Lucca was the character in the game that he felt most emotionally attached to, due to her kindness, dignity, and occasional obliviousness. He also identified the first time Robo and Lucca met as one of his favorite events in the game. When discussing a theoretical game to follow Chrono Cross, Katō discussed an idea where Kid, Lucca's adopted daughter, went on a quest to save her, Crono, and Marle. He ultimately rejected this idea due to his principle that "the past is the past".
