Gemini Black specializes in melee combat, using a customized buzz saw to attack its enemies.
Despite looking nearly identical, Black is apparently a female, while White is apparently a male.
They love the Professor and see him as a father, but they've apparently entered their rebellious phase. Despite this, they take his lessons to heart. As siblings, they greatly care for each other.
They are artificial Martians, created by the Professor and appear as young children with blue hair.