Flight: Aerivar possesses the superhuman ability to fly by means of natural wings, which span 16 feet from wingtip to wingtip, and are fully feathered like a bird's.
Aerial Adaptation: The entire anatomy of Aerivar is naturally adapted to flying. His bones are hollow like a birds, making him weigh far less than usual for a human. His body is virtually devoid of fat and possesses greater proportionate muscle mass than an ordinary human does. His eyes are specially adapted to withstand high-speed winds which would hurt the average human eye. He also possesses a special membrane in his respiratory system enabling him to extract oxygen from the air at high velocities or altitudes.
Aerivar XVIII position regarding Red Raven and humanity varies from an account to another:
Red Raven Comics #1 show Red Raven being adopted by Aerivar XVIII, despite other Bird People's fear that he might cause their end. The entry of Red Raven in Marvel Mystery Handbook 70th Anniversary Special #1 confirms that version. He is also mostly benevolent towards humanity.
In X-Men #44, it is another unnamed Avian who propose to raise him, Aerivar making him responsible for his actions. He is also malevolent towards humanity.
In Sub-Mariner #26, Aerivar see the baby's arrival an omen from the Sky-Gods, but is soon malevolent towards humanity.
Red Raven Comics #1 (May, 1940)
Joe Simon, Louis Cazeneuve
PARENTS AND RELATIVES
Red Raven (ward/foster son)
Marvel Mystery Handbook 70th Anniversary Special #1 (September, 2009) (Red Raven's entry)(Presumed deceased)