Answer:
Lovely and round, I shine with pale light, Grown in the darkness, a ladyโs delight.
I run through hills. I veer around mountains. I leap over rivers. And crawl through the forests. Step out your door to find me.
I can generate fear and some say I come out of your ears. I am as quiet as a mouse but not welcomed in the house.
In a tunnel of darkness lies a beast of iron. I can only attack when pulled back. What am I?
I start new then become old. Start clean but be one dirty. I usually start big then become little.
I flow from the Homerโs mouth when he sees doughnuts.