Dota 2

Dota 2 is a multiplayer online battle arena video game developed and published by Valve. Dota 2 is played in matches between two teams of five players, with each team occupying and defending their own separate base on the map. Development of Dota 2 began in 2009 when IceFrog, the lead designer of Defense of the Ancients, was hired by Valve to create a modernized remake for them in the Source game engine. To maintain it, Valve supports the game as a service, selling loot boxes and a battle pass subscription system called Dota Plus that offer non-gameplay altering virtual goods in return, such as hero cosmetics and audio replacement packs. Dota 2 has a large esports scene, with teams from around the world playing in various professional leagues and tournaments. Valve manages an event format known as the Dota Pro Circuit, which are a series of tournaments that award qualification points for earning direct invitations to The International, the game’s premier annual tournament. Internationals feature a crowdfunded prize money system that has seen amounts in upwards of US$30 million, making Dota 2 the most lucrative esports game. Despite some criticism going towards its steep learning curve and overall complexity, Dota 2 was praised for its rewarding gameplay, production quality, and faithfulness to its predecessor, with many considering it to be one of the greatest video games of all time.
Two spinoff games, Artifact and Dota Underlords were also released by Valve. Dota 2 has also been used in machine learning experiments, with a team of bots known as the OpenAI Five showing the capability to defeat professional players.