Replica is an autonomous, cube-shaped support robot in the anime and manga series World Trigger. Acting as a mentor and adviser, Replica assists Yūma Kuga by providing tactical analysis and vital information during battles. With advanced AI capabilities, Replica can analyze enemy movements, create Trion body parts, and offer guidance in unfamiliar situations. Replica plays a crucial role in helping Yūma navigate the world of Border and serves as a source of wisdom and protection for the protagonists.