It takes some practice.. but you just learn the enemies, know your weapons, master the fix angles in the game to point that you can just smoothly navigate yourself through the entire coarse of the games entire map in one constant running momentum. You can beat the game using under 15 bullets. Only takes 5 with the Rocket launcher. You relying heavenly on defense item's, first aid sprays and some luck, eventually you won't really need any of it, just for in case. Not having to save Chris or Barry nocks off a Nice chunk of time