Navy is a new character introduced in Metal Slug Attack.
Navy was a scientist that worked with the Professor while he was in the Rebel Army. They did not get along well due to their conflicting views. After the Professor defected to the Martians, Navy became the head chief of the science department, and according to Percier, was more interested in pharmaceuticals than Martian research. Despite her position, Navy is unable to recruit researchers for the Rebel cause, unless Abigail allows her to.
Unlike the Professor, Navy is a bit more impulsive and tends to jump into action regardless of her opponent's strength, wanting to prove that she is better than him.
Navy makes her appearance in the Extra Ops "Mad Scientists", where she successfully defends her lab from the Professor, who attacked it in order to learn more about Vita.
In "Sadistic Emotion", Navy attacks the Ptolemaic Army in order to capture and interrogate their supply officer Sisilia per Izabella's request. Upon defeating Veronica and Dragunov, Navy disbelieves Sisilia's claims that her music has restorative powers, only to find out the hard way when the two defeated officers suddenly spring back into action. Knowing that they are outmatched, she drags Izabella away before they would get captured.
In "United Front the 9th", Navy, along with Emma, create the Golden Nokana. However, they are initially unable to find anyone, and Navy is annoyed when one of the reasons why people wouldn't pilot it was because it was golden, as she didn't decide the paint and gold was a powerful color. Vita manages to find a volunteer; Allen O'Neil. The Golden Nokana gets critically damaged in battle and Allen O'Neil carelessly abandons it against her wishes since he believes his platoon is better than any golden weapon.
When Harriot returns to Earth, Navy asks Abigail if she could take the traitor down with the Scrap Tower. Abigail allows her to, though she expresses little faith that she would win. Harriot easily overpowers the Scrap Tower, before Abigail ends their "childish" fight. She then watches as Abigail reinstates Harriot as a double agent.
Navy later oversees a Try Line operation, assigning Jane Doe as the combat medic. This causes Cline to question her decision, due to the fact that Jane appears to be scaring everyone by wanting to replace wounded parts with zombie versions, rather than focusing on treating the injured, and she witnesses her scare a patient back to health. Following the operation, Navy spots Cline outside one of the medical units and asks her where Growth is, as the two are always together. Cline informs her that Growth was wounded during the operation before asking her why she can't get into the medical unit. Navy then informs her that the medical unit they are outside is an intensive care unit.
Sometime after the Try Line operation, Navy calls Loretta, informing her not to destroy the source of mysterious power causing most of the soldiers to succumb to their desires. Loretta flatly refuses her request and destroys the power source, causing her to complain to Grazia, but her complaint goes unanswered.
Following this operation, Navy continues her duties, and is seen talking with a researcher about the progress of one of her latest experiments, apparently unaware that the researcher is actually an android infiltrator. As a result of the infiltrator escaping with potentially vital data and her apparent oversight, she is punished by Vita for her failure.
First appearing in "Cross/You", Navy's past is revealed more thoroughly. Prior to her current position as the head chief, she created Vita and got into an argument with the Professor, who wanted her to put a personality override on Vita because her depression would prevent her from fighting efficiently. Navy refused to, stating that she was alive and that was all that mattered. The Professor threatened to do the modification himself if she didn't do so, but he defected to the Martians by that time, prompting Rebel high command to promote her to the head chief. Despite Vita's initial self-depression, Navy continued to work with her, prompting the cyborg to accompany her due to the care she gave her. She also sets out to destroy Sol Dae Rokker Anima, which she does so successfully, though she soon gets into an argument with Amadeus when he points out that the Professor wasn't just good in combat.
Later on in "False Peace", Navy is seen experimenting on mutants to empower the Rebel Army. One of these experiments fails, and she suddenly recalls the Huge Hermit and asks Abigail to authorize Allen Platoon to retrieve it. They are able to retrieve the Huge Hermit, allowing Navy to perform more experiments.
During "A Christmas Miracle", Navy teaches another researcher how to maintain Vita, since she can't do so in the future as she will eventually die. The researcher puts Vita into a prolonged coma, which would eventually result in the creation of Nova.
Navy began developing Iron Vermilion sometime after experimenting on the Huge Hermit. During one of her visits, Schwarz Metzelei crash-lands onto the facility and starts going on a feeding frenzy. She notices Navy and is excited to eat her since she is different from the others. Vita manages take Navy away temporarily, and she heads into the Iron Vermilion to battle Schwarz. Against Vita's advice, she recklessly attacks the Metzelei, which results in it being destroyed along with Vita being critically damaged. Navy manages to escape with what remains of Vita since Schwarz ended up being distracted by the Iron Vermilion's remains.
- She is the first Box Crank unit to have a Special Rare version.