Avalon is a realm of the cosmos - an "otherworld," if you will. The inhabitants of this world are "faeries" - humanoid superbeings with unprecedented abilities. This realm is governed by councils of the most powerful faeries. They guard the realm of outside threats. "Faerie" is an umbrella term that includes nymphs, elves, druids, mermaids, etc. How do you gain access? There are portals hidden in the cosmos. You just need to know where to look.