Answer:
Once you know it exists, it no longer exists. What is it?
What sphinxes employ and players enjoy.
It flavors your food and divides the year up. What is it?
A setting that proved to be deadly for Abraham Lincoln.
A precious gift, yet it has no end, no beginning, and nothing in the middle.
Two little holes in the side of a hill. Just as you come to the cherry-red mill.
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?