Sega has released a promotional trailer for the game Closers Online, animated by studio SILVER LINK with the background music Cast Your Shell.
Therefore, the game company Naddic developed Closers online and published it in South Korea in December 2014. Sega, in turn, released the game in Japan.
The game takes place in Seoul, after a dimensional portal opens, bringing various monsters into this world. Players control a team of "Closers," psychic soldiers skilled at fighting the monsters and closing the interdimensional portals.