Talk:SE.RA.PH/@comment-28048698-20170503232143/@comment-27545925-20170504024423

You are right. In fact, I'm pretty sure this is directly connected to the main story so comparing it to the Prison Tower event might be more fitting.

As for the story, there is another branch of Chaldea called Seraphics, an oil rig that provides funding for Chaldea's activities. Chaldea has communications with Seraphics every few months. When they try to contact Seraphics this time, the only thing they got was a recorded SOS message. Da Vinci-chan asks one of the staff to use CHALDEAS to get an idea of what's happening to Seraphics. They find out that Seraphics has completely vanished into thin air.

Just as they are confused about the situation, BB hacks into Chaldea and tells them that Seraphics has become a Singularity in the Mariana Trench, 2030. BB tells Guda to Rayshift and resolve the situation. However Da Vinci-chan and Mashu say that Rayshifting into the future is impossible. BB says that it's possible with her help and the three Extra servants decide to go with Guda to protect them. When they start the Rayshift, BB reveals that she tricked them and separates them so that Guda ends up alone and defenseless. BB then says that she digitalised Seraphics and turned it into a copy of the SE.RA.PH. She apparently tricked a lot of Heroic Spirits into this SE.RA.PH and is making everyone fight a Holy Grail War. She's turned it into a battle royale with 128 servants though. So Guda ends up fighting a lot of enemy servants while trying to investigate the truth about what happened to Seraphics and trying to find a way to escape.