I've completed every level w 3/ stars, completed all of the Heroic and Iron Challenges, and recieved every avaialble achievement but I still somehow only have 80 out of 82 available stars.
Can anyone point me in the direction of where those missing two stars would be?
Also, I've spent my stars on every upgrade but still have 18 left. Is there going to be any place to spend these in the future?