During the Black Kat event, there was a Book of Dark Rituals that was sought out by a lot of people. :P
I saw a lot of people looking in T2 for the book, but I think it could only be found in T3, right? T3 is the only place where 5* mats come from, so does that mean all those hours people spent on trying to find it in T2 were wasted?
No, some people found it in T2. The boss is T2 in the first place, anyway.