The easiest way to get a McWorld happy meal code is by purchasing a happy meal at a participating McDonald's. If that is not an option, websites such as mcworldcodes.wordpress.com and mcworldcodeshappymealcodes.blogspot.com occasionally post codes for free.
These codes are used in the McDonald's based McWorld game on happymeal.com. These codes are used to unlock various outfits, credit increases, brand new avatars and in extremely rare cases, certain cards have been known to grant the player unlimited points. Unlimited point cards are part of a limited time promotion and are only available through the purchase of McDonald's Happy Meals, unlike other codes, which can also be obtained online.