A Foulfeather is a Fallen in Oninaki.
Fowl Fallen with insect-like wings. Foulfeathers attack by firing magile from their barrel-shaped beak. They end to retreat when approached, so trying for a close-quarters attack is liable to end in you getting shot.
Encyclopedia of Fallen 1-1
Foulfeathers can accurately measure the distance to their target and determine when to fire, though the sensory organ with which they do this remains a mystery. Reproducing such an organ could lead to great advancements in the medical sciences.