Curse of the Crimson Throne
The flying, purple creatures who make their homes in the the rooftops of Korvosa are similar to pseudodragons, but are actually a local sub-species known as house drakes. They are in constant conflict with the large number of imps brought to the city by the summoners of the Acadamae. Many of Korvosa's nobles decorate their roofs with tiny amounts of precious metals, among them silver-lined weather vanes, shingles, and gutters designed to catch the sunlight to give their homes a distinctive sparkle in the sunlight. By spending years sharpening stings and teeth against these silver-enhanced decorations, or sneaking drinks of holy water from outdoor fonts at various temples, some house drakes have effectively transformed themselves into deadly weapons against the city's imps.