I come from under the hill, and under the hills and over the hills my paths led....

I come from under the hill, and under the hills and over the hills my paths led. And through the air, I am he that walks unseen.
I am the clue-finder, the web-cutter, the stinging fly. I was chosen for the lucky number.
I am he that buries his friends alive and drowns them and draws them alive again from the water. I came from the end of a bag, but no bag went over me.
I am the friend of bears and the guest of eagles. I am Ringwinner and Luckwearer; and I am Barrel-rider.