Zc is a failed trading currency. When I was still on the staff team I urged Chelt to make a new zc shop that would have some need items that players could buy, and then it would have a conversion bucket in the middle to convert the zc to gralats. This way you give people an option to use the zc one last time to buy some new items and to then trade in zc for gralats. The idea was to announce that ZC was being removed a month prior and that this shop would be opened for a month and then all zc would be removed. However more pressing things seemed to come before the zc removal, (Gender options), but its still a decent method of eliminating the currency and rewarding the players. I like the idea of having auctions right after the entire process.