Answer:
Once you know it exists, it no longer exists. What is it?
What gives life and love, and is there till they die? What can hide you and find you, heal you and feed you but should never give up on you?
What falls down but is never injured?
What has a hundred limbs, sometimes leaves, but cannot walk?
You are on an electric train. Which direction will the smoke fly in?
What sphinxes employ and players enjoy.
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?