Answer:
A dragons tooth in a mortals hand, I kill, I maim, I divide the land.
I turn around once. What is out will not get in. I turn around again. What is in will not get out.
I am a fire's best friend. When fat, my body fills with wind. When pushed to thin, through my nose I blow. Then you can watch the embers glow.
What's as small as a mouse but guards a house like a lion?
A time when they're green. A time when they're brown. But both of these times, cause me to frown. But just in between, for a very short while. They're perfect and yellow. And cause me to smile.
Do what he says and you'll be fine, don't and you lose the game.