Belinda Abel was a freelance assassin when she first met Argos. Although his speeches sounded nice, she was not interested in anything but profit. Bia had heard all kinds of justifications for all kinds of murder so there was nothing particularly new to what he had to say. Watching the attack on the British Parliament live on television and seeing people like herself killed by the authorities she felt incredibly guilty. She arrogantly believed had she been there, they might have succeeded. They had given her the name Bia after the goddess of force and power and when Argos showed up on her doorstep for help she gave them all she could. During the time that Mr. Helix was recovering Bia broke into Scotland Yard's holding facility and murdered Winged Beauty.
The work she did for various governments prior to joining The Master Race is part of the reason they have not come after them directly. She personally performed assassinations for many world governments and the 1%. If made public, would ruin many careers in Washington AND the corporate world. Her enemies are waiting for her to expose herself at which time they'll take her and her fellow mutants out permanently.
Along with super strength and durability, she also possesses a variety of other superhuman attributes, including (but possibly not limited to): super speed (50 mph tops), super agility, super reflexes, and super dexterity/coordination. Bia is also able to instantly replicate the physical movement of peak-level humans in her vicinity and perform these movements for up to six hours. Not only does this make her a deadly opponent, but she is also the perfect sparing partner and has made The Master Race a powerful team of combatants.