Answer:
I can run but not walk. Wherever I go, thought follows close behind. What am I?
In a tunnel of darkness lies a beast or iron. It can only attack when pulled back. What is it?
I drift forever with the current and flows to your everyday life. I make living easy but I am good at killing people too.
My days are numbered.
If a man carries my burden they will get crushed to death. Though not rich I leave silver in my track.
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.