Answer:
Once you know it exists, it no longer exists. What is it?
Used to keep prisoners silent and to make temporary repairs on cars.
What devours all and can kill a king. Destroy a town and crushes mountains down?
What starts with a T ends with a T and is full of T?
This became a fashion statement in the garden of Eden.
I'm the source of all emotion but I'm caged in a white prison.
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?