The Mystery Box is vending only a single item ("Silver Hookah") at two price points, 11,198 and 16,187 (I think.)
I am using Windows 7 with the most recent installation of Firefox. I have only my antivirus' security bar and Java as plugins.
This error repeated about 18 times (thanks to Major Drills.)
This is the Mystery Box: http://subeta.net/explore/mystery_box.php
Thanks.
Just checked it out and am getting the same issue. The second price is 16,797 though.
It's not actually a glitch, it's the fact that the shop, Cavern of Curios has a really limited stock, only 65 items and almost all of them have a higher rarity.
Only are below r66 which is considered rare, and the machine is very unlikely to vend those.