Seems like they're preparing a new part of Time Temple.

Although the tutorial for Demon Slayers only show up a small part of the Dark Temple, some hints are in the Game Start page of KMS.



Even the time Goddess herself appears next to the launch button. I really hope i'm not wrong and that she just appears for Demon Slayers, because it'd be pretty stupid only to add all this area, and Rhinne, the Goddess that everyone in there mentions just for a class.

Also for the fact these monsters haven't showed up in this recent patch data, in the login screen, for example, the only monster that appears is the Blue Lyka, on Demon Slayer's prologue, which means these didn't arrive yet.

Really looking forward to the fact Nexon seems to be getting back to focus on Black Mage's encounter, instead of just creating more and more servants.

My theory +1

The Black mage intends to reawaken the Time Goddess to potentialy destroy the world.