Where do you type in Moshi Monsters cheat codes?

Cheating is not allowed on Moshi Monsters.

There is a link at the bottom of the Moshi Monsters game pages that says "ENTER SECRET CODE!" Click on that link and it takes you to a page where you can enter codes. Click on 'Enter Code Here' and enter your code. Then click 'Eat It!' and IGGY will eat your code. If the code is good, IGGY will show you your prize. IGGY will also tell you if the code has already been used. If a code is expired, IGGY will say "Sorry, you can not use that code." Click on 'Eat Another Code' if you have more codes to enter. Click on 'Go To My Room' to return to your room and check your Inventory (treasure chest).