User blog comment:Call me Ken or Accel/Full Burst Nana, Ciel and Gilbert VS. Demiurge (and Prithvi Mata)/@comment-26113680-20151018104008

Just a side information.

The mission name tranlated would be Cocytus.

Here more into on it : https://en.wikipedia.org/wiki/Cocytus

Though, on second thought Ken probably knew it :3