Answer:
I go around in circles but always straight ahead never complain no matter where I am led. What am I?
In a tunnel of darkness lies a beast or iron. It can only attack when pulled back. What is it?
I am a food with 5 letters. If you remove the first letter I am a form of energy. Remove two and I'm needed to live. Scramble the last 3 and you can drink me down.
Dead on the field lie ten soldiers in white killed by one blade yet there was no fight. What are they?
My second is performed by my first. A thief by the marks of my whole might be caught. What am I?
No matter how little or how much you use me, you change me every month.