Answer:
Lighter than what I am made of. More of me is hidden than seen. What am I?
Tear me off and scratch my head what once red is now black.
I belong to you but others use me more often than you do
What goes into the water black and comes out red?
In a tunnel of darkness lies a beast or iron. It can only attack when pulled back. What is it?
Give it food and it will live, give it water and it will die.