Witchcrow

The witchcrow, renowned as a harbinger of ill deeds and misfortune, preys on the weak and spies on the unwary. Clever, manipulative, and avaricious in the extreme, these foul birds have no conscience. Witchcrows strive to steal not only victims’ most cherished possessions, but their hopes and dreams as well. Witchcrows can also hold valuable information - which they provide to Bitter Bettie.
  Witchcrows value arcane magic above all else, not simply as practitioners—the birds certainly have their own innate talent for witchcraft—but also as collectors. An intense covetous streak drives witchcrows to pilfer these things if they sense them among a victims possessions. Often, they single out arcane casters as targets for thievery, closing on casters from a distance with their vanish ability and executing flyby attacks to snatch away any baubles they desire. 
  Prolonged spellcasting (casting spells with a casting time greater than 1 round) often attracts witchcrows in the area. They stalk spellcasters in groups, watching for opportunities to steal from them.