Black Ops 2 introduced a brand new weapon camouflage called diamond. This is an elusive camo and is rarely seen. It requires time and patience to obtain. This article reveals how to get diamond camo for your weapons in BO2.
(Call of Duty: Black Ops 2, PC, PS3, Wii U, Xbox 360)
Actually some of the challenges you don’t have to unlock in sequence mostly the ones dealing with blood thirstys, kills with a car, double kills, etc. i think anything dealing with the number of kills yes those do unlock in sequence. Now this coming from a guy who only has the crossbow gold at the moment and some of my challenges did not go in sequence. So i don’t know about the other weapons.
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easy enough