[0.01T] The Ultimate Visitor

Or is it some temporary event via red telephone booth in Henesys that occurs in event maps in and around Henesys? Or perhaps it's accessible via Mirror Portal?

Judging by everything shown it appears to be just a large event instead of actual content. If it was real content then the new equipment would mean all other equipment would no longer be necessary and/or wanted. There's the fact that it's accessible by any level, like an event. The screen-shots show the quests in the event section as well. This is just pointing out a few things though.

I mean, obviously there's no way to tell for -sure-, but I bet all my meesooz that it's an event.