Answer:
Goes over all the hills and hollows. Bites hard, but never swallows.
Useful tool for who in darkness dwell. Within you, corrupting like a deadly spell.
It's anything but amusing when this body part gets hit.
What's black when you get it, red when you use it, and white when you're all through with it?
What is lighter than what it is made of?
They are many and one, they wave and they drum, Used to cover a state, they go with you everywhere.