Answer:
I have three heads. Cut off one I become stronger. Cut off two I become ten.
I turn around once. What is out will not get in. I turn around again. What is in will not get out.
I run up and down the stairs without moving. What am I?
I am a creature with a βtightβ name.
I am long and slim works in light. Has but one eye and an awful bite.
I build up castles. I tear down mountains. I make some men blind. I help others to see.