Metagame

From Wikipedia: "Metagame, literally "a game outside the game," is a prediction of how others will make decisions in a game based on their personality or their previous decisions. A metagame can exist in any game in which the opposition is human or portrays some sort of artificial intelligence and the competitors make choices. Metagaming is taking advantage of the metagame for purposes of winning more often."

Within Guild Wars, the metagame refers chiefly to the skill selections and profession combinations in builds (solo and team) used to win PvP battles. There are multiple metagames in Guild Wars, including:
 * Guild versus Guild metagame
 * Tournament metagame (also known as Heroes' Ascent or Tombs metagame)
 * Random Arena metagame (less well defined than other metagames, but a metagame exists regardless)

The popularity of builds is more precisely called the environment, though this is also one meaning of the term metagame. The environment, in general, includes all factors that players should take into account when playing the metagame. For instance, Factions introduced Assassins and Ritualists into the environment.