Answer:
My second is performed by my first, and it is thought a thief by the marks of my whole might be caught.
Can be achieved in a car or as a position during conflict
Inside a burning house, this thing is best to make. And best to make it quickly, before the fire's too much to take.
What always comes into the house through the keyhole?
What has one head, one foot, and four legs?
I break away from my pack. I create holes in my victims. I can travel for miles and then disappear. I am part of a dying breed. What am I?