Development

                                               

The first version of Defense of the Ancients was released in 2003 by a mapmaker under the alias of Eul[14] who based the map on a previous StarCraft scenario known as "Aeon of Strife",[12] After the release of Warcraft's expansion The Frozen Throne, which added new features to the World Editor, Eul nor Lamsphadians updated the scenario.[15] Other mapmakers produced spinoffs that added new heroes, items, and features.[14]

Among the DotA variants created in the wake of Eul's map included DotA Allstars, developed by modder Steve Feak (under the alias Guinsoo); this version would become today's dominant version of the map, simply known as Defense of the Ancients.[16] Feak said when he began developing DotA Allstars, he had no idea how popular the game would eventually become; the emerging success of the gametype inspired him to design a new title around what he considered an emerging game genre.[17] Feak added a recipe system for items so that player's equipment would scale as they grew more powerful, as well as a powerful boss character called Roshan (named after his bowling ball) who required an entire team to defeat.[14]

Feak used a battle.net chat channel as a place for DotA players to congregate,[14] but DotA Allstars had no official site for discussions and hosting. The leaders of the DotA Allstars clan, TDA, proposed that a dedicated web site be created to replace the various online alternatives that were infrequently updated or improperly maintained. TDA member Steve "Pendragon" Mescon created the former official community site, dota-allstars.com, on October 14, 2004.[18]

Towards the end of his association with the map, Feak primarily worked on optimizing the map before handing over control to another developer after version 6.01. The new author, IceFrog, added new features, heroes, and fixes. Each release is accompanied with a changelog.[19] IceFrog was at one time highly reclusive, refusing to give interviews; the only evidence of his authorship was the map maker's email account on the official website and the name branded on the game's loading screen.[4] Icefrog now interacts with players through a personal blog where he answers common questions players have about him and about the game.[20] He has also posted information about upcoming map releases, including previews of new heroes and items.[21] In October 2009, Icefrog was hired by Valve Corporation, leading a team in a project that he has described as "great news for DotA fans".[22] Valve officially filed the trademark for "DotA" in August 2010,[23] leading to Steve Mescon's DotA-Allstars company to file a counter application of trademark for the phrase "Defense of the Ancients", in order to gain ownership of the Warcraft III map and to prevent Valve from entitling a sequel.[24]

Defense of the Ancients is maintained via official forums. Users can post ideas for new heroes or items, some of which are added to the map. Players have contributed icons and hero descriptions and created the artwork displayed while the map loads, and suggestions for changes to existing heroes or items are taken seriously; IceFrog once changed a new hero less than two weeks after the new version of the map was released.[4] Versions of the scenario where enemy heroes are controlled by artificial intelligences have also been released. Mescon continued to maintain dota-allstars.com, which by the end of IceFrog's affiliation in May of 2009 had over 1,500,000 registered users and had received over one million unique visitors every month.[18] Due to their separation, IceFrog announced that he would be further developing a new official site, playdota.com, while continuing game development;[25] Mescon closed dota-allstars on July 22, 2010, citing dropping statistics and his new passion for League of Legends as the reason for its end.

Because Warcraft III custom games have none of the features designed to improve game quality (matchmaking players based on connection speed, etc.), various programs are used to maintain Defense of the Ancients. External tools ping player's locations, and games can be named to exclude geographic regions.[4] Clans and committees such as TDA maintain their own official list of rules and regulations, and players can be kicked from matches by being placed on "banlists".[4]