Vullaby is a Pokémon that resembles a baby vulture. It has a plump, stout body covered in dark gray feathers, tiny wings with gray tips, and pink feet with three clawed toes. Vullaby's neck is short and supports a round, pink head devoid of any feathers, except for a crest on the top. There is a collar of fluffy, light gray feathers around its neck. It has a small gray beak and red eyes.
Vullaby protect their rear by wearing a cracked, upside-down skull as a diaper-like undergarment, hence its categorization. Vullaby either finds this bone itself or uses one found for it by Mandibuzz. Its large appetite results in large growth spurts, resulting in Vullaby having to replace their bones, and they often pass older bones down to smaller Vullaby. Vullaby often start petty chats with their own kind on which bones are the most comfortable. Vullaby is known to chase after weaker creatures. Vullaby is a female-only species.
Vullaby and its evolved form were designed by James Turner. According to interviews with Ken Sugimori in Nintendo Dream, Vullaby and Mandibuzz were added late into the development of Black and White, and despite the fact that there were "too many bird Pokémon already", their designs were approved.
Despite Vullaby's Pokédex entries stating that its wings are too undeveloped to let it fly, it can still learn Fly and Brave Bird.
Vullaby is likely based on a vulture chick. The bone armor it wears is similar to a baby's diaper, with physical similarities to a human's skull. Its frequent growth spurts are another connection to babies, which grow at much higher rates than adults.
Vullaby may be a combination of vulture and lullaby (which are often sung to children) or baby.
Valchai may be a combination of vulture and child.