Unlock the Gold camouflage for all weapons in a specific class (e.g. Assault Rifles, SMGs, Sniper Rifles, etc.) in Multiplayer mode to unlock the Diamond camouflage for all weapons in that class. For example, get the Gold camouflage for all Specials (Assault Shield, Ballistic Knife, Combat Knife, and Crossbow) to unlock the Diamond camouflage for all Special weapons.