The following is a revision of the rules and fluff for the Ceilicans, as presented in Changing Breeds, a Werewolf: the Apocalypse 20th anniversary book. The W20 rewrite changed most of their yava to the weaknesses listed here, but still kept some obnoxious restrictions ... like having to change their identity once per year but not giving them any special ability to do so.
Ceilicans are one of the most well-known breeds of shapechangers, but much of what people (even other shapechangers) think they know about them is wrong.
Cats were often said to be the familiar spirits of people accused of witchcraft during the middle ages, and were put to death along with the "witches." Fera call the shapechanging cats of this time Ceilicans, and believe them to be descended from the Cait Sith, fey cats of legend. They are thought to have learned magic from the fey and from actual mages, and to be hiding in modern society using extremely powerful glamours. If you catch one, it's said, you can ask for a magical boon.
Most of that's true. But in truth, Ceilicans' magical powers aren't quite up to granting wishes, and many of their Gifts revolve around hiding from those who would try to exploit (or destroy) them.
After being hunted nearly to extinction, the "witch cats" have learned to hide their true nature in two ways.
First, they have access to a level one Gift which lets them appear to be of mixed racial or breed heritage, making them appear slightly "off" to some but usually no more than that. This allows them to blend in to different human societies, or appear to be small mongrel wildcats such as you might find in a group of other cat shapechangers. This gift requires a roll of Manipulation + Subterfuge, and the expenditure of 1 point of Gnosis, which doesn't return until the Ceilican dispels the glamour. While it is active, they can't benefit from the Pure Breed background.
Second, many Ceilicans know a rite that can replace their identity with a new one. Their memories and appearance are altered, and they may re-allocate skills at a rate of one dot per success rolled. Their Merits and Flaws remain, but their pryio and Backgrounds must be changed to different ones once the rite is completed. If any memories of their past life remain, they seem like dreams or half-remembered stories.
Ceilicans have three unusual weaknesses, all of which resemble legends told about them. Reciting a Ceilican's name backwards six times is supposed to be able to kill them; it really just makes them uncomfortable. The sound of churchbells is supposed to strike them deaf, when in reality it just entrances them for a moment. Finally, cold iron is said to burn their skin like a brand; as it turns out, extremely pure iron affects them this way, regardless of its temperature. Most Ceilicans are vulnerable to silver as well, like other shapechangers, but many -- called "moon cats" by some -- treat it as their plaything.
A Ceilican's feline form is the size of a housecat or small wildcat. Ceilicans with the Pure Breed background look like sleek, black domesticated cats, with emerald green eyes that seem to glow in the dark.