Answer:
I have a head and a tail but no body. What am I?
What is at the end of a rainbow?
I am longer than a decade and shorter than a millennium
I begin and have no end. Eventually I will be the end of all that has begun.
I am in the past never in the future. I don't exist but have existed. I saw what you saw and that is what I will ever see.
Special abilities and brightly colored underwear are all you need to be one of these.