>>421637433.5/10
Good color scheme.
Utterly impractical design: doesn't really look as if it needs arms at all; the arms are extra heads for some reason; body too rotund to seem like a creature that has no real means of locomotion other than flight.
Designed by name-based flavor/theme rather than with any coherent design roadmap in mind: stage 1 is a quadruped; stage 2 is the exact same quadruped but with two heads; stage 3 is OP pic. If anything, Hydreigon should have been a terrestrial beast looking more like a hydra with legs than this bizarre, bulbous bat-thing.