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Smilegate and Cover announced that the Hololive English Vtubers Calliope Mori and Nerissa Ravencroft perform the theme song for the new game Chaos Zero Nightmare. The performers’ duet is called “Over//Ride.” While the game is currently in the pre-registration phase on Android, iOS, and PC via Stove, the track’s music video is on YouTube and streaming on services like Amazon and Spotify.
Here’s the new song “Over//Ride” from Hololive Vtubers Calliope Mori and Nerissa Ravencroft.
We’ve heard Calliope Mori perform theme songs for projects before. One of the most recent ones was Suicide Squad Isekai.
This also isn’t the only time Hololive Vtubers Calliope Mori and Nerissa Ravencroft performed a duet together. The two performed a cover of “Bocca della Verità” together for the 3D concert Requiem for Love.
As for Chaos Zero Nightmare, there is a promotion tied to pre-registration at the moment. If two million people sign up, everyone gets the four-star character Amir at launch. They’ll also get 20 Rescue Anchor items for the gacha. As of July 13, 2025, they hit 200,000, which means everyon egets 10 Advanced Battle Memories.
Chaos Zero Nightmare will come to the PC and mobile devices in 2025. The App Store page has an “expected” October 15, 2025 release date associated with it.
