Dota 2 players have already more than doubled the prize pool for The International 4 by purchasing in-game Compendiums, driving the total winnings up to nearly $3.9 million as of publication.
Valve noted that, within the first 24 hours, player contributions to the prize pool for this year's tournament outmatched last year's total player contributions. Two months remain for players to buy Compendiums before The International kicks off.
The in-game Compendiums went on sale Friday, combining tournament bracket predictions with slots for players to select their favorite teams and players. Players can level up their compendiums by watching matches or buying points with real cash, unlocking rewards like an exclusive in-game courier model and battle point booster.
Tickets for The International went on sale on April 3, with prices ranging from $99 to $499. The tournament will be held in Seattle's KeyArena from July 18 to 21 and will host 11 of the best competitive DotA teams, as well as four regional qualifiers.
Valve previously released a feature-length documentary on professional gaming on Steam. Titled 'Free to Play', the internally-produced documentary follows three professional Dota 2 players from different continents (Asia, North America, and Europe) as they compete to win $1 million in the first Dota 2 International Tournament.