The original Caligula, titled The Caligula Effect in the west, first launched for PS Vita in June 2016 in Japan followed by May 2017 in the west. A remake subtitled Overdose followed for PlayStation 4 in May 2018 in Japan, and PlayStation 4, Switch, and PC via Steam in March 2019 worldwide.
While a sequel has yet to be officially announced, The Caligula Effect series producer Takuya Yamanaka teased a sequel back in June 2020.
In related news, Bandai Namco Entertainment filed trademarks for “Platinum Edition” in English and Japanese on December 16, as well as “Maou to Ryuu no Kenkokutan” (The Tale of the Demon King and Birth of the Dragon Nation). (Update 8:17 p.m.: Bandai Namco has announced SD Gundam G Generation Cross Rays Platinum Edition for PlayStation 4 and Switch.)