Character skin for completing all Screen Hit challenges.
The Blockbuster challenges contain a secret. After finishing the given set of challenges from each week, you will receive an award - a loading screen. There is a total of seven of these, and each shows a location of a collectable. The secret provides a chance of getting as many as ten Battle Stars, which translates into one full level. The above map shows all the collectables (loading screens) that you have to collect in order to reap the special reward.
Leveling up is not everything, though. After collecting all seven stars, you will also get a legendary outfit for your character - The Visitor, along with a special backpack to match it. You can check out the dank skin on the screen above. As in the cases of Carbide and Omega, it can be modified to a certain extent.