She was one of the main villians when the show started to lose its prime. While we don’t see much of her Dalmatians origins, but she is pretty evil.
She joins Rumplestiltskin, Ursula, and Maleficent in a quest to make the bad people get their happiness.
She wasn’t too powerful, but she did have the magic ability to control dogs or whatever.
She dies and shows up in the Underworld, still her horrid self.