What's the difference between a demigod and a spirit?

Is it just a matter of power? Udyr demonstrated to be able to attune and become both Volibear and Ornn, that are known demigod, but he also became many other creatures, being these other animals that are not known for being Demigods (to us) Are these normal spirits, or are they also demigods from another land?
Report as:
Offensive Spam Harassment Incorrect Board