Complex sentence: The Lightning Bird is widely feared as a witch's familiar, it's considered an evil creature because it does the bidding of witches, if a Witchdoctor dispatches an Impundulu it can cause illness and bad luck to a person.
Split into simpler sentences: The Lightning Bird is widely feared as a witch's familiar. It is considered an evil creature because it does the bidding of witches; if a witch doctor dispatches an Impundulu it can cause illness and bad luck to a person.