The beautiful Ms. Oxygen was a veteran member of the MPA, who was known for her strategies and analytical skills in battle. However, an unknown traumatic experience caused her to resign her post. She spent the rest of her days making a living working as the director of the Minimus Power Plant until she witnessed Hydrogen go through a molecular change in his fight against one of the Synvasion Force’s elite officers—a change that she believes will turn for the worse if not treated properly. For Hydro’s sake, she immediately insisted that she came back to work for the MPA.

Based on her experience, Oxygen was appointed second in command of Hydrogen’s unit where she, along with Dr. Xenon, will brief you on your missions and direct you on where you need to go. She also shares her knowledge of the types of mutants and enemies you encounter along the way to give Hydro and his team a better idea on how to defeat them. Unknown to everyone else, she secretly shares an individual link with Hydrogen. It was installed so that she can teach him about the strengths and weaknesses to his strange new ability: to bond with the remaining electrons of fallen enemies to increase his stats.

Oxygen is usually calm and collected; nothing can really phase her out of that personality unless it was an extreme travesty. She's also very strong-willed, being able to look danger in the face and stand her ground. One thing she is annoyed with, however, is the constant barrage of hit-ons she receives from the Synvasion Force officer, Tin. She isn't much of a fighter, but she can get herself out of tight situations if the time calls for it. She can summon bubble-like barriers strong enough to lift objects or people and carry them off to another location. The barriers are also strong enough to block incoming attacks as long as they're not sharp enough to penetrate through it.