Dota

The Dota series began in 2003 with Defense of the Ancients (DotA)—a mod for Blizzard Entertainment's Warcraft III: Reign of Chaos—created by the pseudonymous designer "Eul".[39] An expansion pack for Warcraft III, titled The Frozen Throne, was released later that year; a series of Defense of the Ancients clone mods for the new game competed for popularity. DotA: Allstars by Steve Feak was the most successful,[40] and Feak, with his friend Steve Mescon, created the official Defense of the Ancients community website and the holding company DotA-Allstars, LLC.[41] When Feak retired from DotA: Allstars in 2005, a friend, under the pseudonym IceFrog, became its lead designer.[42] By the late 2000s, Defense of the Ancients became one of the most popular mods worldwide, as well as a prominent esports game.[43] IceFrog and Mescon later had a falling out in May 2009, which prompted the former to establish a new community website at playdota.com.[44] Valve's interest in the Dota intellectual property began when several veteran employees, including Team Fortress 2 designer Robin Walker and executive Erik Johnson, became fans of the mod and wanted to build a modern sequel.[45] The company corresponded with IceFrog by email about his long-term plans for the project,[46] and he was subsequently hired to direct a sequel.[47] IceFrog first announced his new position through his blog in October 2009,[48] with Dota 2 being officially announced a year later.[49]

Valve adopted the word "Dota", derived from the original mod's acronym, as the name for its newly acquired franchise. Johnson argued that the word referred to a concept, and was not an acronym.[47] Shortly after the announcement of Dota 2, Valve filed a trademark claim to the Dota name.[50] At Gamescom 2011, company president Gabe Newell explained that the trademark was needed to develop a sequel with the already-identifiable brand.[51] Holding the Dota name to be a community asset, Feak and Mescon filed an opposing trademark for Dota on behalf of DotA-Allstars, LLC (then a subsidiary of Riot Games) in August 2010.[41] Rob Pardo, the executive vice president of Blizzard Entertainment at the time, similarly stated that the Dota name belonged to the mod's community. Blizzard acquired DotA-Allstars, LLC from Riot Games and filed an opposition against Valve in November 2011, citing Blizzard's ownership of both the Warcraft III World Editor and DotA-Allstars, LLC as proper claims to the franchise name.[52] The dispute was settled in May 2012, with Valve retaining commercial rights to the Dota trademark, while allowing non-commercial use of the name by third-parties.[53] In 2017, Valve's ownership of franchise was again challenged, after a 2004 internet forum post from Eul was brought to light by a Chinese company known as uCool, who had released a mobile game in 2014 that used characters from the Dota universe.[54] uCool, who was previously involved in a lawsuit with Blizzard in 2015 for similar reasons,[55] along with another Chinese company, Lilith Games, argued that the forum post invalidated any ownership claims of the intellectual property, stating that the Dota property was an open-source, collective work that could not be copyrighted by anyone in particular.[54][56] Judge Charles R. Breyer denied uCool's motion for summary dismissal, with Blizzard filing motions to dismiss all claims against uCool and Lilith with prejudice.[54][57][58]

An early goal of the Dota 2 team was the adaptation of Defense of the Ancients's aesthetic style for the Source engine.[49] The Radiant and Dire factions replaced the Sentinel and Scourge from the mod, respectively. Character names, abilities, items and map design from the mod were largely retained, with some changes due to trademarks owned by Blizzard. In the first Q&A session regarding Dota 2, IceFrog explained that the game would build upon the mod without making significant changes to its core.[47] Valve contracted major contributors from the Defense of the Ancients community, including Eul and artist Kendrick Lim, to assist with the sequel.[59] Additional contributions from sources outside of Valve were also sought regularly for Dota 2, as to continue Defense of the Ancients's tradition of community-sourced development.[60] One of the composers of Warcraft III: Reign of Chaos, Jason Hayes, was hired to collaborate with Tim Larkin to write the original score for the game, which was conducted by Timothy Williams and performed and recorded by the Northwest Sinfonia at Bastyr University.[61][62] Valve had Half-Life series writer Marc Laidlaw, science fiction author Ted Kosmatka, and Steam support employee Kris Katz write new dialog and background lore for the heroes.[63][64] Notable voice actors for heroes include Nolan North, Dave Fennoy, Jon St. John, Ellen McLain, Fred Tatasciore, Merle Dandridge, Jen Taylor, and John Patrick Lowrie, among others.[65]

The Source engine itself was updated with new features to accommodate Dota 2, such as high-end cloth modeling and improved global lighting.[49] The game features Steam integration, which provides its social component and cloud storage for personal settings. In November 2013, Valve introduced a coaching system that allows experienced players to tutor newer players with in-game tools.[66] As with previous Valve multiplayer games, players are able to spectate live matches of Dota 2 played by others,[66] and local area network (LAN) multiplayer support allows for local competitions.[67][68] Some of these events may be spectated via the purchase of tickets from the "Dota Store", which give players in-game access to matches. Ticket fees are apportioned in part to tournament organizers.[69] The game also features an in-game fantasy sports system, which is modeled after traditional fantasy sports and feature professional Dota 2 players and teams.[70] Players are also able to spectate games in virtual reality (VR) with up to 15 others, which was added in an update in July 2016.[71] The update also added a hero showcase mode, which allows players to see all of the heroes and their cosmetics full-size in virtual reality.[72]

As part of a plan to develop Dota 2 into a social network, Newell announced in April 2012 that the game would be free-to-play, and that community contributions would be a cornerstone feature.[73] Instead, revenue is generated through the "Dota Store", which offers for-purchase cosmetic virtual goods, such as custom armor and weapons for their heroes.[74] It was also announced that the full roster of heroes would be available at launch for free.[75] Until the game's official release in 2013, players were able to purchase an early access bundle, which included a digital copy of Dota 2 and several cosmetic items.[76] Included as optional downloadable content (DLC), the Dota 2 Workshop Tools are a set of Source 2 software development kit (SDK) tools that allow content creators to create new hero cosmetics, as well as custom game modes, maps, and bot scripts.[77][78][79] Highly rated cosmetics, through the Steam Workshop, are available in the in-game store if they are accepted by Valve. This model was fashioned after Valve's Team Fortress 2, which had earned Workshop designers of cosmetic items of that game over $3.5 million by June 2011.[75] Newell revealed that the average Steam Workshop contributor for Dota 2 and Team Fortess 2 made approximately $15,000 from their creations in 2013.[80] By 2015, sales of Dota 2 virtual goods had earned Valve over $238 million in revenue, according to the digital game market research group SuperData.[81] In 2016, Valve introduced the "Custom Game Pass" option for creators of custom game modes, which allows them to be funded by way of microtransactions by adding exclusive features, content, and other changes to their game mode for players who buy it.[82]

Dota 2 includes a seasonal Elo rating-based matchmaking system, which is measured by a numerical value known as "matchmaking rating" (MMR) that is tracked separately for core and support roles, and ranked into different tiers. MMR is updated based on if a player won or lost, which will then increase or decrease respectively.[83] The game's servers, known as the "Game Coordinator",[84][85] attempts to balance both teams based on each player's MMR, with each team having roughly a 50% chance to win in any given game.[83] Ranked game modes with a separately tracked MMR are also available, which primarily differ from unranked games by making MMR publicly visible, as well as requiring the registration of a phone number to their accounts, which help foster a more competitive environment.[83][86] To ensure that each player's ranking is up to date and accurate, MMR is recalibrated around every six months.[87][88] Players with the highest possible medal rank are listed by Valve on an online leaderboard, separated into North American, European, Southeast Asian, and Chinese regions.[89] The game also includes a report system, which allows players to punish player behavior that intentionally provides a negative experience.[90] Players who get reported enough or leave several games before they conclude, a practice known as "abandoning", are then placed into low priority matchmaking, which remains on a player's account until they win a specific number of games, and only groups them with other players who also have the same punishment.[91][92] Other features include an improved replay system from Defense of the Ancients, in which a completed game can be downloaded in-client and viewed by anyone at a later time, and the "hero builds" feature, which provide integrated guides created by the community that highlight to the player on how to play their hero.[93]