Instructions
Move the mouse cursor so it points directly at an enemy. Shooting enemies anywhere on their body will inflict damage.
Click the mouse button to fire your weapon. If you shoot an enemy in the body, but he does not die, you need to shoot him again.
Move the mouse cursor so it points directly at a vulnerable area on the enemy's body. If your first shot hits him in the leg, aim at the opposite leg. If your first shot hits him in the torso, aim for the head.
Continue shooting until the enemy disappears, which indicates he has been killed.