Special Missions or Offer Wall offers are third party offers within the game that allow all Nonstop Knight players to earn free Gems.
Special Missions are triggered randomly while you are actively playing the game. They are indicated by a red gift box on the left side of your screen. As soon as you tap on this box, the Special Mission screen will open. There, tap on "GO" to be redirected to a page with various third party offers of which you can pick one to earn free Gems.
Feel free to contact our Customer Support if you have problems accessing or navigating the Special Missions.