From Webkinz Insider Wiki
On September 9, 2015 Mazin' Hamsters was retired.
The object of Key Craze is to find keys, bring them back to the treasure chest, and see if they will open the chest. It is similar to the timed Zum Challenge in the Mazin' Hamster Hamlet. If you open the chest you will be awarded a prize. It is a timed challenge, so you have 3 minutes to find a key that will open the treasure chest.
When you find a key, 10 seconds are added to your time. Your hamster can only pick up one key at a time though so try to get back to the chest as quickly as possible.To help you get back to the chest, a blue arrow pointing towards the chest appears near the top of your screen.
Not all keys open the chest. If your key does not open the chest, you will be able to search for another until you find one that works or the time runs out. When you find a key that does open the chest, you will be awarded a random prize from the list below.