The digital tome is just $10 and is there to help fans navigate the tournament events. The next stretch goal is at $2m and rewards a custom HUD for all Compendium owners.
At $2.2m a Taunt item accompanied by a "brand new animation" is rewarded. $2.4m yields a vote on participants in an 8-player Solo Championship at The International.
The highest stretch goal so far is $3.2m which lets Compendium owners "choose the next hero we release." The Interactive Compendium is a "virtual passport" that keeps its owners fully comprised of everything going on at The International tournaments. It lets fans predict match winners, receive item drops and vote like crazy.
Valve is yet to name the unlock at stretch goal 6 ($2.6m).
For more information on the Interactive Compendium check out the.