Complete all 15 Chapters on Hard difficulty. It is fairly easy since you do a lot of driving and a fair amount of shooting. Here are some tips to keep you alive:
- Stay in cover at all times! A couple bullets may graze you and kill you.
- Shoot at enemies when they are reloading. If they are in cover, be ready to shoot once they come around the corner to shoot again.
- If you can, aim at a location you know enemies will run through. (Ex. A door or hallway) Be ready on the trigger.
- If you keep failing in a spot, try to use a different tactic. (Ex. A different gun or moving to the opposite end of the hall)
- Never go to shoot or come out of cover when you are getting fired upon. You will kill yourself in the process.
- Have enough ammo before starting a mission. Don't run out of ammo in the middle of a firefight.
- Make good use of the cover system. You can slide to pieces of cover if you are in a tight squeeze.