Dota 2

Dota 2 is a multiplayer online battle arena (MOBA) video game in which two teams of five players compete to destroy a large structure defended by the opposing team known as the "Ancient" whilst defending their own. As in Defense of the Ancients, the game is controlled using standard real-time strategy controls, and is presented on a single map in a three-dimensional isometric perspective. Ten players each control one of the game's 127 playable characters, known as "heroes", with each having their own design, strengths, and weaknesses. Heroes are divided into two primary roles, known as the core and support.

Cores, which are also called carries, begin each match as weak and vulnerable, but are able to become more powerful later in the game, thus becoming able to "carry" their team to victory. Supports generally lack abilities that deal heavy damage, instead having ones with more functionality and utility that provide assistance for their cores, such as providing healing and other buffs. Players select their hero during a pre-game drafting phase, where they can discuss potential strategies and hero matchups with their teammates. Heroes are removed from the drafting pool and become unavailable for all other players once one is selected, and can not be changed once the drafting phase is over.

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". An expansion pack for Warcraft III, 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, and Feak, with his friend Steve Mescon, created the official Defense of the Ancients community website and the holding company DotA-Allstars, LLC. When Feak retired from DotA: Allstars in 2005, a fellow website user under the pseudonym IceFrog, became its lead designer.

By the late 2000s, Defense of the Ancients became one of the most popular mods worldwide, as well as a prominent esports game. com. Rob Pardo, the executive vice president of Blizzard Entertainment at the time, stated that the company had discussed with IceFrog in person the possibility of developing a MOBA but that they felt they were not ready to commit to such an endeavor. 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.

Dota 2 received "universal acclaim" according to review aggregator website Metacritic, and has been cited as one of the greatest video games of all time. In a preview of the game in 2012, Rich McCormick of PC Gamer thought that Dota 2 was "an unbelievably deep and complex game that offers the purest sequel to the original Defense of the Ancients. Rewarding like few others, but tough." Adam Biessener, the editor who authored the announcement article for Dota 2 for Game Informer in 2010, praised Valve for maintaining the same mechanics and game balance that made Defense of the Ancients successful nearly a decade prior and Quintin Smith of Eurogamer described Dota 2 as the "supreme form of the MOBA which everyone else working in the genre is trying to capture like lightning in a bottle".

The most frequently praised aspects of the game were its depth, delivery, and overall balance. Chris Thursten of PC Gamer described the gameplay as being "deep and rewarding".

A month prior to its launch, Dota 2 was already the most played game on Steam with a concurrent player count of nearly 330,000, which outweighed the number of players for the rest of platform's top ten most-played games combined. It remained as the most played game by concurrent players on the platform for four years, having a peak of over one million and never dropping below first place for any extended period of time until being surpassed by PlayerUnknown's Battlegrounds in 2017. Viewership and followings of professional Dota 2 leagues and tournaments are popular, with peak viewership numbers of the International in the millions. Some Asian schools and universities, such as the Asia Pacific University of Technology & Innovation in Malaysia, have held courses teaching students the fundamentals and core skills to use for the game. Dota 2 has been a part of multi-sport events in Asia, such as the Asian Indoor and Martial Arts Games and Southeast Asian Games.

The popularity of Dota 2 led Valve to produce apparel, accessories, figurines, and several other products featuring the heroes and other elements from the game. In addition, Valve secured licensing contracts with third-party producers; the first of these deals concerned a Dota 2 themed SteelSeries mousepad, which was announced alongside the game at Gamescom 2011. In September 2012, Wētā Workshop, the prop studio that creates the "Aegis of Champions" trophy for winners of The International, announced a product line that would include statues, weapons, and armor based on characters and items from the game.