Isn't this illegal?

There are tons of chinese knockoffs like this due to China's lax copyright infringement laws and lack of regard for international laws.

Sometimes, they even make it to NA before the original game does! Ragnarok Online had Xenepic.(sp?) And more recently, Elsword had Fists of Fu.

.....Maple Story is too big in China for such a thing though. This has to be one of the mobile games.