Silas, or Dr. Wolfsong, is a Sinox, a wolf Gootraxian with purple fur. He has a light purple underbelly, with slightly darker purple on his hands, lower legs and neck fluff. He also has mint green lines on his face, chest, wrists and knees as well as mint green fur inside his ears that glow during blackouts. In addition, he also has green tips on his hair which also glow. His hands and feet are also a mint green, separated by the rest of the arms with a small, white outline.