Moon Festival Cards are Limited Edition cards introduced in Beta Build 28323 that are available as drops during the Moon Festival Seasonal Event, and also occasionally in the Player Market. These four unique cards have no practical purpose ingame and are only used as trading cards between different players. However, if you are able to obtain a full set of all four cards, they can be put in the Nanoforge to create an exclusive Pet, the Mooncake Box. In order to craft this pet, you must put in one of each of the cards. It will not work if you put in, for example, four Lotus Root Mooncake cards.