The Hat Upgrade.

Like some strange hybrid of a MOBA and Team Fortress 2, Dota 2 is going to be free to play with its own user-generated workshop. Just like TF2, users can create their own gear to be used in-game if Valve approves of it. But unlike TF2, these items have no effect and all champions are unlocked from the beginning, creating an even playing field with shiny cosmetic additions to motivate purchase.