Guild Wars 2 is a MMORPG and GW2Spidy is an online trading post where players can purchase items. Players can use their game account to login and view all the items and listings. An API is available that makes the site data available for use in other websites and applications. Methods available include Type List, Discipline List, Rarity List, Item List, Item Data and more. The API uses RESTful calls and responses are formatted in JSON, JSONP and CSV.
MMOG designer ArenaNet is transforming its popular Guild Wars 2 by opening up its code to be redeployed by users via APIs. Players can make their own iOS and Android apps as well as build tools to use in the game. The Guild Wars 2 API will likely become extremely popular among its huge user base for what Time Magazine called "#1 VideoGame of 2012."