Leaderboard

I also tried doing this with the regular Shop Wizard (I don't have Neopets Premium), and I found one that you haven't brought up: There may be a few more I may have missed. EDIT: Came across a petpage on the Neoboards that has (almost) every item likely pertaining to the plot (WARNING: Contains spoilers, click at your own risk):

Mosaic Toy

Day "two"(?) is still locked so my guess is it will be at least a day and a half to collect the void essence. One of the achievements is also to collect 50 void essence so we might even have more than one day in between locations. There's also a timer on 7 days (for weekly bonus rewards?) and 5 visible locks (but there are arrows, pointing to more to come).