Cytus is a collection of rhythm games developed by Taiwanese game developer Rayark. The original Cytus rhythm game was first released on the iOS platform on 12 January 2012. The game was later released on Android on 7 August 2012. A port for PlayStation Vita and PlayStation Mobile, titled Cytus: Lambda, was released on 26 June 2013. An arcade version titled Cytus: Omega in collaboration with Capcom was revealed at JAEPO in February 2015 and was set for location testing in July 2015, but was ultimately canceled on 30 March 2018. A sequel game, Cytus II, was released on 18 January 2018, for iOS and March 2018 for Android. A remake of Cytus Alpha (stylized as Cytus α) was also released for the Nintendo Switch on 25 April 2019.
Plot
Cytus
The story of Cytus is carried through its 10 main chapters as well as a prologue. The story is told in-game through various cutscenes that are unique to the chapter title songs; individual songs within each chapter are at most only marginally relevant to the plot, except for a limited few. The plot features the disaster and the protagonist's struggle with identity.
The story revolves around the protagonist, Vanessa, who lives in a 22nd-century world where robots with human memories are the only things remaining. While the other living humans are killed by a mutant alien virus that came from outer space. Later, she determined that she is a one of person that entering memories transfer services powered by ExtenLife to extend their life and live with her loved ones. The transferring is interrupted due to limited memory space and her emotions are corrupted. As the human emotions are stored in the form of music in "Cytus", by playing the songs, the robots are able to revive their human emotions. When she revives it, she is sad about it. She tries to write a mini program with Lua to delete her emotions from their memory and starts to travel around the node to delete the emotions from the other robots that called "The Operators". While in travel, she found the cyro-pods that store the living humans who survived the alien virus by freezing themselves into the pods. Vanessa try to awaken the freezing humans and give a mission to rebuild the human society again.
Cytus II
Cytus II, the sequel to Cytus, takes place about seven hundred years after the establishment of the new human society called "The New Age (N.A.)" (as ending of Cytus). And establised A.R.C. to create a virtual Internet space called Cytus (stylized as cyTus). As more and more people used the virtual internet, more and more musicians held concerts on iM, a social networking service. One musician, Aesir (stylized as Æsir), decided to hold a large virtual concert in Node 08, one of the many nodes in Cytus. Attendees of the event included Paff (stylized as PAFF), a popular singer, Neko Asakura (stylized as NEKO#ΦωΦ), a famous streamer on iM, and Robo Head (stylized as ROBO_Head), an AI robot. A bunch of top musicians performed, but the organizer, Aesir, was nowhere to be seen, even after the end of the event. By browsing through iM and through each character's private "OS logs", players can unlock new songs and gain insight into the story of Cytus.
Later, Paff and her media company, Monophonic Entertainment, announced the date for her annual event, PAFFCON. Tickets for her event sold out quickly. At the event, while Paff was performing Gravity, a same song that she performed in Aesir Fest, she collapsed and was sent to the hospital, where she would wake up a few days later and start recovering.
While Paff was in the hospital, one of Neko's streams got hacked and DDoS attacked by Aesir. Neko was arrested by Node 08's Administration Bureau because she was suspected of launching a widespread attack on her fans. Meanwhile, Robo Head later discovers that his memory of Aesir was corrupted, and starts data recovery. People wanted to know who was responsible for the hacking. After Robo Head completes data recovery, he learns that Aesir did show up at the event and that they wiped everyone's memory of Aesir after he finished performing, and this is a same attack method on the Neko hacked streams.