The world's most lucrative video game contest is being held, with contestants vying for a share of the $10.9 million (£6.3 million) prize fund.
The tournament, known as The International, sees gamers compete against one another through a game called Dota 2.
The title is a multiplayer online arena game for the PC, where each player assumes the role of one of 107 different heroes. Each character must work in teams to destroy their rival's "ancient," an artefact inside a team's fortress, while defending their own.
The final match will see two Chinese teams, NewBee and Vici Gaming, battle it out for the grand prize.
The successful team of five players will receive $5 million, the runners-up $1.4 million, with $4.5 million shared between the remaining 19 teams taking part in the tournament.
The developers of the game, Valve, donated $1.6 million of the prize money for the Seattle-based event, with the rest of the funds being raised by the game's many users.
The final is a hotly anticipated affair as online tournaments are increasingly becoming spectator events.
Video streams of the matches have been shared online and some bars and gaming centres have been hosting parties for groups wishing to view the contest.
The final is also set to be shown on one of the ESPN channels.
Michael O'Dell, manager of the UK's Team Dignitas, said, "This year has certainly been the banner year for eSports, with massive tournaments in Dota, League of Legends and CS:GO (Counter-Strike: Global Offensive). And there are more to come. The scene is very vibrant right now."