World of Warcraft

World of Warcraft is the largest massively multiplayer online role playing game today. With millions of players contributing to the community over the last eight years, the game has become far bigger than the mechanics that make it up.

Core Gameplay
Broken down into its simplest parts, the goal in World of Warcraft is about defeating enemies. In order to accomplish this goal, players are given two main ways of interacting with each other: healing themselves and their party, or damaging the enemy. The individual actions and enemies can vary greatly depending on the situation, but all interactions can be seen as belonging to one of these two categories.

This interaction boils down to the player damaging the enemy and defeating them before they are killed, while adventuring on their own. When multiple people group together to take on larger foes, individuals will take on different roles to give the entire party a better chance of success. For example, one player may act as a healer, spending all of their time making sure that their party can fight for as long as they can, while another will focus more on drawing the attention of the enemy so that the rest of the party can spend all of their energy on offense. These roles are normally not successful on their own but in a party they are the most important members of the group.

As groups grow in size, roles become more differentiated. Without going into specific functions, roles split into main tanks, off tanks, tank healers, raid healers, single-target damage, area-of-effect damage, melee damage, ranged damage, crowd control, and as many others as the players can invent. This diversification on its own is not emergent, but the consequences are. Due to the breaking up into these roles, groups of 10-25 players can defeat enemies 100-1000x stronger than a single player can handle.

Specific Emergent Incidences
Other unexpected events have happened in the game as well. The most famous of these is the Corrupted Blood incident. Essentially, a damaging curse was created that would quickly spread to every member of a group fighting a particular enemy. It was designed so that it should not have left the dungeon, but the programmers did not catch every way it could escape. Ultimately, the curse made its way to one of the populated cities where it spread just like a plague would. Low level characters were quickly killed, and most others were severely crippled. Since the plague would not have died out on its own, the solution came in the form of a quick patch to the game and a server restart.

In-Game Economy
Along with diverse social emergent behavior, World of Warcraft has created its own in-game economy. In addition to the roles each person takes, the game allows players to make choices about their characters clothes. Different items have different benefits for the player and can often be traded between players. The items are dropped by enemies in game at set rates. Based off this simple set of drop rates and which classes can use what type of gear, a complex in-game economy has grown involving an in-game auction house and several chat channels dedicated to trade among the players.

Players have been known to trade services for goods in game, like assisting lower level players in quests for part of the items dropped or for a set amount of gold.

http://www.wowecon.com/ - A website dedicated to tracking the in game economy of WoW.

http://greedygoblin.blogspot.com/2010/02/unique-rules-in-wow-economy.html - A blog dedicated to analysis of the WoW in game economy.

Monetary Value of in Game Gold
The in game gold has even developed and external monetary value in the real world. People are selling quantities of in game gold they spend time accumulating for real money. This has become a major point of contention for players of WoW.