Nebula

History
Nebula was one of Wither's greatest allies due to the fact that she was a Shape-shifter. Unlike Wolfy and her friends, Nebula can transform into anything she imagined and had no known elemental magic. She created the Darkshadow, a dense toxic fog to wipe out populations of Light Fairies, but Geronimo threw a magic gem into Nebula's volcanic lair to destroy her and her cloud of smoke.

Physical Descriptions
Not much was known about her past, but as a Shape-shifter, she probably wasn't able to properly control her magic abilities, so she constantly transformed into something else, permanently concealing her true form.

Personality
Nebula was said to be a wicked and cunning Witch, who stood for evil. Not much is known of her past.