Answer:
I hide in a dark tunnel awaiting my time. I can only be released by pulling back. Once released I may do unstoppable damage.
I have a gown but I'm not a priest; I have a crown but I'm not a king.
I have green hair a round red head and a long thin white beard.
I have been the beginning of ideas for all time yet I am just one simple small object the things that you can use me for can be frustrating and also I can be pretty. I have some of the most valuable thing in the world on me yet almost everyone owns me.
The most famous dinner
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.