• Nymphs, from all realms sky, woods, land, water, underworld. Asteriae, Dryads, Naiads, Napaeae...
• Fairies
• Elves
• Valkyries
• Mermaids
• Huldras
• Gnomes
• Dwarves, those who live in Nidavellir you know...
• Goblins, kobolds, leprechauns... such house spirits
• Dragons, both western and eastern
• Giants, jotuns, titans, stone giants
• Trolls
• Werewolves, and other shapeshifters
• Vampires
• Koi (Chinese carp)

p.s. I believe in all of them!