Answer:
I am brown and sticky
I invade your home once a yearโฆbut only if youโve been good.
What asks but never answers?
Whoever made me don't want me. Whoever bought me don't need me. Whoever use me don't know me.
I build up castles. I tear down mountains. I make some men blind, I help others to see. What am I?
Give it food and it will live, give it water and it will die.