15 usd for the DLC. Quite steep :/
For that price there had better be at least 2 new areas. I know there are two new bosses so it seems likely. I assume it will also add new weapons and armor and maybe even magic and a ring or two. For that price I am hoping for around 15-20 hours of play.
Any less then that and I am not sure the price could be justified.
From finally tweeted and announced they are releasing the DLC in Japan as well as the PC edition, October 25th.