Cait Sith is an enemy from Final Fantasy IV: The After Years. It is not a dangerous foe unless left alone, at which point it will constantly use its Blaster attack to inflict Paralysis or Instant Death to random party members. It is therefore advised to not defeat all other enemies first and leave at least one alive while defeating the Cait Sith.
Cat sìth (meaning "faerie cat", pronounced "Kat Shee") is a fairy creature from Celtic mythology, said to resemble a large black cat with a white spot on its breast. Legend has it that the spectral cat haunts the Scottish Highlands.
The legends surrounding this creature are more common in Scottish folklore, but a few occur in Irish. Some common folklore suggested that the Cat Sìth was not a fairy, but a witch that could transform into a cat nine times.