Nightshade

Nightshade is a slender, long-legged black she-cat with short, soft fur, and bright green eyes.

Hollypaw's Vision
Nightshade is seen by Hollypaw fighting Doveleap at the battle, easily outmatching her. Hollypaw fights Nightshade, but cannot win against her. Doveleap then joins in, and together Hollypaw and Doveleap chase Nightshade away from them.