Answer:
Open me, and you can't see me without a mirror. Close me and you can't see me at all. What am I?
Although glory but not at my best. Power will fall to me when the man who made me dies.
What can be as big as an elephant but weighs nothing?
When I come in from sea to shore twenty paces you'll see No less no more.
I am a tool for fairies.
Though not a plant, has leaves. Though not a beast, has spine. Though many wouldn't need this thing, It's more valuable than wine.