The 2015 International Compendium has been released, giving Dota 2 players the opportunity to contribute to the prize pool of the Dota 2 International Championship. 25% of each Compendium sold goes to the prize pool, and as the prize grows, more items are unlocked for owners of the big glowing book.
As of this moment, the prize pool is over $3 million, meaning owners receive The International Coin Charm and Cursor Pack, the ability to vote on All-Stars, and Immortal Treasure I, which contains one Immortal item and the slim possibility of some other rare treasure. You can take a look at the full list of rewards here.
The 2014 International's prize pool was initially $1.6 million, with sales of the Compendium and other purchases ultimately raising the prize to nearly $11 million. $5 million went to the winner, team Newbee. We'll see if 2015's total trumps that.