Answer:
Golden treasure I contain guarded by hundreds and thousands. Stored in a labyrinth where no man walks Yet men come often to seize my gold. By smoke I am overcome and robbed then left to build my treasure anew.
I shoot but never kills
I am a protector. I sit on a bridge. One person can see right through me, while others wonder what I hide. What am I?
What is easy to spot but hard to find?
I must be broken before you can use me.
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.