Cytus

Cytus is a story-based rhythm game divided into several chapters. Gameplay makes use of a system called the Active Scan Line, in which a black line moves up and down across the screen. Black circles called notes appear on the screen as the song plays, and must be interacted with when the scan line passes over them. Depending on the type of note, they may need to be tapped, dragged, or held. Hitting notes with good timing and building up a combo increases the player's score, which is then used to calculate their rank.

Songs are divided into sets called chapters, each of which tells a story. The first ten chapters, I through X, form the main plot of Cytus. They tell the story of a future in the 22nd century in which humanity has been wiped out by a virus. In an attempt to preserve something of themselves, humans uploaded their memories into robot bodies; however, technological limitations necessitated a separate storage system for emotions. The memory storage system, Cytus, allows robots to access their human emotions in the form of music. The story follows a robot named Vanessa as she comes to terms with her new life and identity as a robot.

Several chapters exist outside the main story, most of which need to be unlocked through in-app purchases. Each of these chapters tells an isolated story, which is sometimes related to another game by the same developers.