English patch notes:
Each player will now receive a piece of diamond dust upon completion of Akh Afah Amphitheatre (Extreme).
Japanese patch notes:
極シヴァ討滅戦において、コンプリート時に「氷神の氷晶」がドロップするようになります。
Diamond Dust now drops upon completion of Akh Afah Amphitheatre (Extreme)
Translation and highlight is mine.
So which is it? English patch notes make it sound too good to be true.