1A. A common Jackhob, and his human employer. Jackhobs are stupendously intelligent. They are on bar, if not above with imps intelligence-wise, though they don't use tools and trap as often. This specimen is male, as shown by the colourful, fanning head quills.
1B. A Jackhob in flight, compared to a Faefly and a Striped Harpy.
2A. A male Faefly shows off his mad skills in wing-having by having wings. Faelfies cannot fly, only glide, like they're mammalian contempory flying Squirrels.
2B. Faelfy in flight.
3A. A female striped Harpy, sporting her bland and generic head quills. She is the heaviest modern flying animal, with a weight (and height) just under that of an adult human male. Male harpies are somewhat smaller than the females, with brighter colours and fanning quills.
3B. A poorly drawn in-flight harpy showing the true immensity of the creature.