The older a vampire becomes, the more they begin to take on animalistic characteristics, (a process known as regressing). Kakistos – Greek for "worst of the worst" – is so old that his hands and feet have become cloven.
Kakistos arrived in Sunnydale with his accomplice, Mr Trick. They are hot on the trail of Faith and are eager to kill the new Slayer. Kakistos had already killed Faith’s Watcher, while she looked on, helpless. Buffy initially suspects that Faith’s arrival in Sunnydale at the same time as Kakistos is not a coincidence, but eventually begins to trust her. With Buffy’s help Faith is able to confront Kakistos. Buffy’s stake has no effect, but Faith kills the vampire when she runs him through with a fence post!
