AeroFluff

Overview

Equal parts machine and organic creature, the experimental project to fully hybridize creatures and planes was a success.  What they didn't count on was their creations breaking out of their lab, quickly multiplying, or creating their own society.  They're not harmful, usually, and in fact make great companions if you can get them to trust you.

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They can change size and shape, mostly between plane-sized and animal-sized.  They have varying amounts of fur and various body shapes, as well as varying plane parts.  They can breed (somehow) and pass traits.  As with animals, this requires a male and female pair.  Rarely, they can be born genderless or with various other oddities.  Unlike a plane, their wings can vary in position, though they still fly like a plane would.  They are generally capable of shifting to either have or hide engines or weapons (if they have any), but if they have a propeller (or several) or engines on their wings, they can't hide those.