Achlys is a young juvenile nightcrawler and the fastest member of the Sprites. He bears a nightcrawler resemblance but has glowing cyan eyes.
Unlike his family, Achlys wants to be different from the rest of his kind, prompting him to run away from home. When he runs, he turns into a cloud of black smoke. Like Nami, Achlys hates the sun and likes being out at nighttime but doesn't mind the day as long as he has shade or a cover.
He fights with a black spear.
Trivia:
Achlys's name comes from the hero Achilles.
He is the first young night crawler.