Chase Zikens is one of Runo Sakaki's friends.
Chase has neck-length blue hair with four spikes, two bigger ones on the front pointing downward and two smaller ones pointing sideways behind the first ones, each lined with a magenta streak. He has green eyes.
He usually wears a flight jacket and jeans.
Chase may initially appear cold and distant, but in reality he's just a reserved boy of few words. Ever since young age, he despised any bullying and/or picking on weaker people, and has a reputation of a Dueling bully hunter. However, he sometimes takes it slightly too far, accidentally hurting his opponent. For this reason, many kids usually avoid him thinking he may be violent and anti-social. Chase doesn't blame anyone beside himself for this, and grew up lonely but at the same time wary of getting too close to others himself.
Despite coming from the Synchro sector of Paradise City, Chase seems to be nervous about the idea of Riding Duels for some reason, and never bought himself a Duel Runner, commenting that he "prefers keeping his feet on the ground".
Chase first appeared in Child of Synchro. Runo convinced him to try the Duel Runner she had built in the past months together with her parents, since she has just passed the junior riding test. However, they happened to meet their friend Samantha on a road testing her own Runner. After a short argument, the two rival girls challenged each other to a Turbo Duel, with Chase reluctantly pulled along as Runo forgot about him in the heat of the moment. Throughout the Duel the boy rooted for Runo as she was repeatedly cornered, until Sam finished her by revealing a much to everyone's shock. He then watched from afar the two girls receiving the congratulations of their parents and shaking each other's hand in respect.
Runo met Chase the first day of middle school. Runo was curious after hearing the rumors about him, and decided to try to befriend him. Chase, while a bit reserved towards her at first, soon decided to accept her after he understood she was well-meaning, and now hang out occasionally. Despite his aversion to riding, he can't never manage to bring himself to deny Runo to take him to go roaming around the city on her Duel Runner.