Various Tips and TricksIn order to advance to the next region, you have to take out the boss enemies in the Black Ops missions.
Keep in mind that completeinf the primary and support missions is the best way to progress.
Always aim for headshots and multi-kills!
You don't need to account too much for the movement speed of your target. Just line up their noggin in your crosshairs and pull the trigger.
Don't try to use a sniper rifle in a mission that specifically calls for a shotgun.
Complete the daily challenges for extra cash.
If you have enough money to upgrade an item do it.
Use one of these upgrades to step up your game:
The Spotter instantly marks all enemies on the field.
The Slo Mo slows down time for the remainder of the level, making it much easier to land headshots.
The Piercing bullets will make your bullets kill anything they hit in one shot, regardless of hit location.