The article below is based on non-localized content only available in Japanese.
As such, all information in this article is based on fan-contributed translations.
Sengoku Asuka ZERO (戦国アスカZERO) is a Japanese city building RPG mobile game published by ORATTA for iOS and Android devices on June 4th, 2015. Since its release, the game has hosted collaborations with other popular anime and video game franchises. From December 1st to December 17th, 2017, the game hosted a collaboration with Danganronpa 3: The End of Hope's Peak High School, in which characters from the series could be collected.
Sengoku Asuka ZERO is an iOS/Android game based in feudal Japan, in which a type of black magic has caused military generals who run the different areas of Japan to act strangely and aggressively. Using rock-paper-scissors style type match-ups, the player uses warriors - all female - to defeat the military generals in battle around Japan in order to reunite the country. The player earns currency which can in turn be used in a gacha to earn new warriors. The player also builds an empire in their home village in which all the characters they have collected can be seen and interacted with, earning loyalty with the individual characters as well as additional bonuses. Over time, the game has featured collaborations with many popular anime and video game franchise, with female characters from the franchises being added into the game for limited periods.On November 27th, 2017 it was announced that Sengoku Asuka ZERO would feature a collaboration event with Danganronpa 3: The End of Hope's Peak High School would run from December 1st - December 17th 2017, revealing some of the featured characters' limited edition cards on a daily basis on the official twitter account, @zeroasuka. An official website was also launched, and it was revealed that logging in during the event's duration would grant players a free Junko Enoshima ★4 card.
On the day of launch, a Twitter competition began in which players could win autographs of the voice actors and can badges featuring the card art by retweeting a specific tweet.
The cameo appearances by each character were all voiced by their original Japanese voice actors, Chiwa Saitō (Aoi Asahina), Kana Hanazawa (Chiaki Nanami), Ami Koshimizu (Ibuki Mioda), Megumi Toyoguchi (Junko Enoshima), Yōko Hikasa (Kyoko Kirigiri), and Ai Kayano (Mikan Tsumiki).