Answer:
To unravel me you need a simple key, no key that was made by locksmith's hand. But a key that only I will understand.
A hole leading in, a hole leading out, we connect to a cavern that is slimy all throughout. What are we?
What comes once in a minute, twice in a moment, but never in a thousand years?
It holds most knowledge that has ever been said. But is not the brain, is not the head. To feathers and their masters, it's both bane and boonΒ One empty, and one full.
What is it something that you always have but you always leave behind?
If lightning strikes an orchestra who is the one most likely to get hit?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?