Blanche "Blondie" Sitznski was born in Pittsburgh, Pennsylvania. She worked as a steelworker until executives at the Roxxon Oil Company selected her to become a special agent in covert operations. She was already well-adjusted to villainy, as she was the calisthenics instructor at the criminal trainer Taskmaster's Academy. It was there that she trained several women in hand-to-hand combat, most notably Diamondback and Snapdragon. She was eventually taken to Roxxon's Mutagenic Laboratory and bioengineered by Roxxon's Mutagenics Division to have various permanent serpentine features. Her entire skeletal structure was laced with an artificial adamantium, giving her the ability to elongate her arms and legs, which she uses to constrict her enemies. She had also been surgically given gills, which allows her to breathe underwater. She has tiny scales on her face, neck, chest, and back, and small fins on her lower cheeks.