Birdragon

Randomly decided to draw up a head concept for the dragons of Eren, which are neither bird nor reptile but the stage between those two: dinosaurs. Specifically, the major clade of Erenic dragons are descended from scansoriogypterids, a bizarre family of tiny theropods from Jurassic China with membranous patagia resembling the wings of a dragon.
More about Eren's dragons will come soon, once I've gotten off my demotivated butt and drawn some more of them.