Instance dungeon

In MMORPGs, an instance dungeon is a special area, typically a dungeon, that generates a new copy, or instance, for each group that enters the area. This ensures that there will never be competition (kill stealing, spawn camping) over mobs within the instance and that player characters receive a minimum of lag. Instance dungeons may contain stronger than usual mobs and sought-after equipment.

Games that have been known to use instancing include EverQuest, Anarchy Online, City of Heroes and Guild Wars. The latter uses instancing extensively to help make the product free of monthly fees.

World of Warcraft and Dark Age of Camelot also use this for Dungeons, but do not or only partly generate it randomly.

The use of instancing is a hotly debated topic among the MMORPG industry. Brad McQuaid wrote an article on the topic that can be found here: Brad McQuaid on Instancing.

EVE Online uses no instancing (apart from socalled deadspace missions, which are instanced for the player) and only one game server. The highest number of players that have concurrently logged into EVE Online recently reached 22,020 on January 2nd, 2006 at 20:44. This is the current world record for highest number of players connected to a single game server without the use of instancing. CCP should consider scrapping this system, though, as EvE has become utterly unplayable due to the number of macro users that are ignored because they provide income to CCP via subscription. The lag throughout EvE has forced the Developers to try and migrate players into less safe and ergo less populated areas of space so that the load on their hardware can be more balanced. This is instead of actually upgrading the hardware as is desperately needed.

Currently World of Warcraft has the largest player base. According to rough calculations servers become full at 2,400 players. After which a log-in queue is utilized, barring players from joining the server until others have left.