Captain Kei Nagase (ケイ・長瀬 Kei Nagase), callsign "Edge", was an Osean fighter pilot, captain, and the second-in-command of the Osean Air Defense Force's Wardog Squadron (later Razgriz Squadron). Nagase was still in training at the time of the Circum-Pacific War's outbreak, but her piloting skills dramatically improved over the course of the war.
She initially served under Captain Jack Bartlett until he was shot down during Operation Gyre on September 27, 2010. From that point forward, she served under Blaze and loyally protected him until the end of the conflict.
Nagase was the second youngest Wardog member and a dutiful pilot. Despite her unwavering sense of duty, she maintained strong anti-war sympathies and was an avid supporter of the pre-war disarmament and anti-proliferation policies enacted by Osean President Vincent Harling. Throughout the war, Nagase hoped to see peace quickly restored with as few casualties as possible.
Nagase was born in the Osean Federation in 1987. Little is known about her life prior to joining the Osean Air Defense Force sometime in her late teens or early twenties. When she was young, Nagase was fascinated by the Arkbird spacecraft, which she referred to as the "white bird of peace", and frequently studied its blueprints. Her favorite childhood book was the fairy tale A Blue Dove for the Princess. Some of the pages in her tattered copy had become illegible over time, leading Nagase to attempt to write in the missing passages from memory.
At some point, Nagase was assigned to Heierlark Air Force Base to begin preliminary flight training, along with Alvin H. Davenport and Blaze. Sometime prior to September 2010, Nagase achieved the rank of 2nd Lieutenant and was assigned to Sand Island Air Force Base. She began participating in training exercises, though she was still considered a rookie pilot by her instructors—Captain Bartlett, in particular, expressed his belief that Nagase's flying would surely get her killed in combat.
Pre-war engagements and open war
Main article: 2010 Osean airspace intrusions
On September 23, 2010, at 1109hrs, Nagase and several other rookies were performing a training exercise over Cape Landers, when they were attacked by unknown hostile fighters. During the engagement, Nagase avoided the hostile fighters and attempted to fight back against her attackers. In the end, only she, Bartlett, and a journalist named Albert Genette survived. That evening, Bartlett chose Nagase as his number two wingman so he could "keep an eye on [her]".
The following day, Wardog Squadron—now consisting of Bartlett, Nagase, Davenport, and Blaze—intercepted an SR-71 of unknown origin that had penetrated Osean airspace. Upon intercept, Nagase and the other Wardog pilots were engaged by more unknown fighters. In direct violation of orders, Bartlett ordered Nagase and the others to engage the hostiles, which were shot down with no Osean casualties.
Three days later, on September 27, Nagase and her squadmates scrambled from Sand Island to intercept several reconnaissance UAVs west of their position. Once again, unidentified fighters ambushed Wardog, but Nagase and the other Wardog pilots shot down all the hostile bogeys. Suddenly, the spy vessel, which had launched the UAVs, fired a surface-to-air missile at Nagase's F-5E Tiger II. She frantically maneuvered to avoid it, but was unable to evade. Bartlett directed his F-4G Wild Weasel into the missile's path, causing it to begin tracking him; Bartlett was subsequently hit on his right wing and forced to bail out over the Ceres Ocean.
Shortly thereafter, Wardog was dispatched to defend St. Hewlett, which had fallen under attack following Yuktobania's declaration of war on Osea. During their ingress towards the naval port, AWACS Thunderhead placed Nagase in command of Wardog Squadron; she refused to comply and gave command to Blaze, whom she swore would not befall the same fate as Bartlett had earlier. Nagase successfully shot down several Yuktobanian aircraft and survived the engagement. That evening, Nagase and her squadmates were joined by Airman First Class Hans Grimm in their defense of Sand Island against a Yuktobanian air raid.
On September 30, Nagase survived the Scinfaxi's burst-missile attacks over the Eaglin Straits and subsequently withdrew to Heierlark, North Osea for refueling; upon arriving, Nagase discovered that she and her squadmates had become the most experienced pilots in the war thus far. The following day, Nagase and Wardog escorted a group of rookie pilots from Heierlark to McNealy Air Force Base in western Osea. Nagase was privately apprehensive that the rookies were being deployed to reinforce the nation's west coast, despite their inexperience.
On October 3, Nagase flew with Wardog to defend Basset Space Center, which was attempting to equip the Arkbird with a laser-cannon module. Nagase lamented that the "White Bird" was to be used in war, rather than the peaceful purposes for which it had been constructed. In spite of her reservations, Nagase performed her duty, and the launch was a success. Following Wardog's defense of Sand Island and the sinking of Yuktobania's submersible carrier Scinfaxi on October 4, Nagase and her squadmates were promoted to 1st Lieutenant.
Akerson Hill incident
Main article: Akerson Hill incident
On October 22, Nagase and Wardog were deployed on a routine patrol mission along Akerson Hill's northern coastline. At 1616hrs, an OADF transport, callsign "Mother Goose One", made contact with Wardog. Nagase and her squadmates escorted the transport through the Osean Coastal Defense Force's automated anti-aircraft system towards the northern coast. After a spy in the crew killed the pilot and wounded the copilot, Nagase became communicating with a man who identified himself as "Mr. Cargo". Nagase instructed Mr. Cargo on how to perform an emergency landing, and the aircraft came safely to the ground.
Having realized by then that Mr. Cargo was actually the Osean president, Nagase asked Harling if he "really [had] to use that beautiful white bird" for the war, and expressed her desire to see his "bridge of peace span into outer space." Harling reassured her that with Osea and Yuktobania on even terms now, the peace negotiations would proceed more smoothly. Nagase's faith in the president was temporarily reaffirmed, and she repeated her desire to see "[no] more young men or women lose their lives."
Invasion of Yuktobania
On October 31, Nagase and Wardog supported the Osean Army's amphibious invasion of mainland Yuktobania. Several days later, on November 4, Nagase and her squadmates reported to Oured for questioning in regards to an unauthorized attack on Yuktobanian civilians that had occurred two days earlier. Wardog, which had been the only known OADF unit operating in the area at the time, became the suspected culprits. During the hearing, Nagase denied Wardog's involvement, and Grimm testified that true malefactors referred to themselves as the "8492nd Squadron". Their statements were disparaged by the tribunal, which firmly reasserted that the air force did not possess any squadron with that designation. When reports reached the courtroom that Yuktobania had launched a series of retaliatory attacks on Osean civilians, Nagase and the rest of Wardog were sent to suppress them.
On November 14, Nagase and her squadmates were dispatched to the Razgriz Straits to eliminate the Hrimfaxi submersible carrier and its burst missiles, which were inhibiting the Osean Army's progress. The engagement ultimately resulted in the sinking of the Hrimfaxi, and earned the Wardog pilots a new nickname: "The Demons of Razgriz". For her role in sinking the Hrimfaxi, Nagase received another promotion to the rank of Captain.
Missing in action; search-and-rescue
Three days later, Nagase participated in an Osean POW rescue mission in the Glubina region of Yuktobania. During the operation, Nagase was shot down by an enemy SAM. The Sea Goblin gunship attempted to rescue her, but crashed in the blustery conditions. As the storm intensified, the Wardog and the other Osean air units were forced to withdraw from the area and postpone the rescue efforts.
Nagase survived being shot down and managed to locate the gunship's surviving crewmen. She tended to their wounds and found shelter to shield them from the snowstorm overnight until help could arrive. The following morning, at 0959hrs, a search-and-rescue operation was mounted for Cpt. Nagase and the Sea Goblin crew; however, the Yuktobanians also dispatched air and ground patrols to search the area for the missing Oseans.
Nagase hid the crew and avoided capture through a combination of running, hiding, and leaving misleading footprints in the freshly fallen snow. By the time the Osean rescue units had located her, Nagase had subdued a Yuktobanian soldier with her M9 sidearm. She and the crewmen were safely airlifted out of the area and later recovered from their ordeal.
Betrayal and escape from Sand Island
On December 6, Nagase and her remaining wingmen were ambushed by the 8492nd Squadron over the Vladimir Mountains. Upon returning to base, Nagase and Blaze decided to inform the adjutant base commander, Major Allen C. Hamilton, of what had happened. Nagase believed that Hamilton would be more commiserative than the base commander, Colonel Orson Perrault, who openly mocked President Harling for his anti-war policies.
When they met Hamilton, however, he accused them and 2nd Lt. Peter N. Beagle ("Pops") of being Yuktobanian spies; realizing that Hamilton was in league with the 8492nd, Nagase punched him and rendered him unconscious. She and Blaze then slipped out of the building and cut the power, giving Pops, Grimm, and Genette an opportunity to escape. Nagase and the others eventually rejoined, commandeered four Hawk training jets, and escaped Sand Island.
After eluding the 8492nd over the Solo Islands in the northern Ceres Ocean, the Wardog fugitives were intercepted by Marcus Snow. Snow signaled for them to bail out, and Nagase and her comrades ejected before their planes were shot down; according to official OADF records, she was "Killed in Action".
The Ghosts of Razgriz
- "I know all about the Arkbird. I was in love with it... I used to stare at the blueprints all the time."
- ― Kei Nagase
After being rescued by the Sea Goblin helicopter team, Nagase and the other fugitives were brought to the OFS Kestrel, under the command of Captain Nicholas A. Andersen. Two days later, Nagase helped free President Harling from his confinement in southern Belka. Following this, Nagase was placed under the president's direct command as the second-in-command of the renamed Razgriz Squadron. Over the coming weeks, Nagase helped eliminate the nuclear warheads that the Grey Men planned to use on Osea and Yuktobania, destroyed the Arkbird, and supported the effort to free the Yuktobanian Prime Minister from his imprisonment in northern Yuktobania.
On December 29, Nagase participated in the Battle of Sudentor, which resulted in the destruction of Gründer Industries' tunnel network beneath the Waldreich Mountains and the SOLG control facilities within it. The following morning, Nagase and her fellow Razgriz pilots were dispatched to intercept and destroy the falling SOLG over Oured Bay. During their approach, Nagase and her wingmen were intercepted by Ofnir and Grabacr Squadrons, leading to a heated dogfight that ended with the Belkan aggressors' destruction. Together, the Razgriz pilots destroyed the falling SOLG before it could annihilate Oured.
It was revealed that Nagase, at an unspecified point after the Circum-Pacific War, became an astronaut under the callsign Pilgrim 1. In 2019, after Trigger foiled the last of the Erusean radicals' plans, although not physically seen, she sent a transmission, thanking him for allowing her ship a place to dock. 
- Nagase's character was originally developed by Kazutoki Kono, who was also responsible for her personality and character traits.
- In the first few missions of AC5, unlike the other wingmen, Nagase tends to remain close to the player's aircraft regardless of the Wingman Commands issued; this reflects her in-story promise to never "lose another flight lead."
- Nagase bears an uncanny resemblance to Reiko Nagase, a prominent character in Bandai Namco's Ridge Racer series.
- Nagase is comparable to Yellow 4, in that both pilots shared a deep devotion to their flight leaders and would not allow harm to come to them.
- Nagase has a couple of references to James Bond. Her aircraft number is 007, and her introduction to the Major during "Heartbreak One" mirrors how Bond introduces himself in the movies: "Nagase. Kei Nagase."
- ↑ F-14A Tomcat `Ace Combat Wardog Squadron` (Plastic model) Package3.
- ↑ Hasegawa 1/72 F-14A "Wardog" plastic model kit decal sheet.
- ↑ 3.0 3.1 Cutscene 10, Ace Combat 5: The Unsung War.
- ↑ WORLD / OSEAN FED / K. Nagase, ACES WEB. Published February 29, 2004. Retrieved September 8, 2016.
- ↑ 5.0 5.1 White Bird (Part II), Ace Combat 5: The Unsung War.
- ↑ 6.0 6.1 Cutscene 02, Ace Combat 5: The Unsung War.
- ↑ 7.0 7.1 Cutscene prior to Narrow Margin, Ace Combat 5: The Unsung War.
- ↑ Shorebirds, Ace Combat 5: The Unsung War.
- ↑ Open War, Ace Combat 5: The Unsung War.
- ↑ Ending cutscene, Open War, Ace Combat 5: The Unsung War.
- ↑ Narrow Margin, Ace Combat 5: The Unsung War.
- ↑ First Flight, Ace Combat 5: The Unsung War.
- ↑ Ending cutscene, Rendezvous, Ace Combat 5: The Unsung War.
- ↑ Cutscene 07, Ace Combat 5: The Unsung War.
- ↑ Cutscene prior to White Bird (Part I), Ace Combat 5: The Unsung War.
- ↑ Front Line, Ace Combat 5: The Unsung War.
- ↑ Handful of Hope, Ace Combat 5: The Unsung War.
- ↑ Ending cutscene, Handful of Hope, Ace Combat 5: The Unsung War.
- ↑ Cutscene 11, Ace Combat 5: The Unsung War.
- ↑ Demons of Razgriz, Ace Combat 5: The Unsung War.
- ↑ Ice Cage, Ace Combat 5: The Unsung War.
- ↑ 22.0 22.1 Cutscene 15, Ace Combat 5: The Unsung War.
- ↑ White Noise, Ace Combat 5: The Unsung War.
- ↑ 24.0 24.1 Cutscene 18, Ace Combat 5: The Unsung War.
- ↑ Final Option, Ace Combat 5: The Unsung War.
- ↑ Ending cutscene, Final Option, Ace Combat 5: The Unsung War.
- ↑ "Aces, Demons, and Ghosts: Mysterious Heroes of the Belkan Conflict", OBN Journal (Special Issue). Published July 2014.
- ↑ Cutscene 19, Ace Combat 5: The Unsung War.
- ↑ Cutscene 20, Ace Combat 5: The Unsung War.
- ↑ Cutscene 21, Ace Combat 5: The Unsung War.
- ↑ ACES, Ace Combat 5: The Unsung War.
- ↑ The Unsung War, Ace Combat 5: The Unsung War.
- ↑ Dark Blue, Ace Combat 7: Skies Unknown.
- ↑ Interview with Kazutoki Kono, Director of Ace Combat Infinity, MCM BUZZ. Published May 25, 2014. Retrieved May 31, 2014.