No, the Inika masks aren't rare. That they were used only one year, that doesn't make them rare... Idk = short for "I don't know"... Well, if you have the normal-blue Ruru (not the light-blue collor of Nokama's mask), than it's probably rare, because thats a misprint from 2001.Or do you mean the Great Blue Ruru from the Karzahni set?I wish I did for either.