Gunslinger Stratos

is a series of third-person shooter video games developed by Byking and Taito and published by Square Enix, that debuted in arcades on July 12, 2012, with the scenario provided by Norimitsu Kaihō (from Nitroplus) based on a concept by Gen Urobuchi. It uses Silicon Studio's Orochi game engine, and runs on the Taito Type X³ arcade system board.

Its sequel,, was released on May 12, 2016.

A sequel to the second game, titled, was announced to be released in 2016 for Windows PC. The servers were closed on March 29, 2016

An anime adaptation of the game, known under its expanded title,, was announced and made its premiere on April 4, 2015. The opening theme is "Vanilla Sky" by Mashiro Ayano and the ending theme is "Mirai" by Garnidelia.

Plot
The story revolves on a group of gunslingers, each from the two universes who participate in Operation Stratos, particularly on a group of four childhood friends: Tohru Kazasumi, Kyōka Katagiri, Kyōma Katagiri, and Shizune Rindo, who all must confront their own flaws and differences when they battle their alternate selves in order to survive.

Official

 * Official Sites
 * Official PC Game Site
 * Official Arcade Game Site
 * Official Anime Site

Other Sources

 * MyAnimeList