The International, the world's largest Dota 2 championship tournament, commences on Friday with group stage play. This year the field would be competing for a $1.6 million prize pool, but that's been fattened by a million thanks to the sale of a virtual item to their fellow gamers, and the pot may increase.

The Dota 2 Interactive Compendium, which has been on sale for almost three months, allows fans to make predictions for the tournament and create fantasy teams within the game. Additionally, $2.50 of each sale (the thing costs $10) goes into the tournament's prize pool. That pool just surpassed $2.6 million.


Valve sweetened this with stretch-goal incentives, and six of the seven have been claimed so far. The latest gives a Compendium owner a new immortal item, in addition to five other perks unlocked up to now.

The last one is unlocked at $3.2 million, which would double the original prize pool. About 435,000 Compendiums have been sold so far; another 204,000 would need to be sold in the final four or five days of the campaign to hit the last goal. But with this thing functioning as a kind of virtual tournament program, who knows, interest may indeed surge that much as The International draws near.

For those competing, first place will get at least a million, second $250,000, and third $150,000. How the prize pool bonus will be split has yet to be announced.

Dota 2 users contribute $1 million to prize pool [Destructoid]