Ace Combat 3: Electrosphere is a combat flight simulation video game developed and published by Namco for the PlayStation. The third game in the Ace Combat franchise, it was released in Japan on May 27th, 1999 and in Europe and North America by January 21st, and March 7th 2000, respectively. Players fly fighter aircraft and must complete a variety of mission objectives, such as destroying squadrons of enemy planes or protecting a base from an invading unit.

Namco directors Takuya Iwasaki and Atsushi Shiozawa designed Electrosphere to be visually distinct from other combat flight simulators, using Ace Combat 2 as a base for the game's ideas and mechanics. The storyline was designed to be a core aspect of the game, and to serve a proper purpose by directly affecting the gameplay. Electrosphere carries a futuristic science fiction-inspired landscape and world compared to the modern-day theme of its predecessors. The game is infamous for its drastic differences in content in the Japanese and international releases; Namco intended to retain the Japanese version's two-disc campaign and larger story, but due to financial constraints the game was cut down for North America and Europe.

Though it had a small marketing campaign and little promotion, Electrosphere shipped over one million copies. The Japanese release received positive reviews and was seen as ambitious in its design. International releases were more mixed, with critics expressing confusion towards the lack of content and bland gameplay. In retrospect, Electrosphere has been well-received, with critics identifying and appreciating its ambition, story, and changes to the gameplay of the series.

Ace Combat 3: Electrosphere is a combat flight simulation video game. Like its predecessors, it is presented in a more arcade-like format in contrast to other flight sim video games. Unlike most other entries in the series, a greater focus on realism was applied to the aircraft's energy conservation, with players having to avoid tight turns and steep inclines lest they burn off airspeed and enter a stall, which were notably difficult to recover from compared to later entries. Players pilot one of 23 aircraft in both releases. On the Japanese release, they may fight across four factions and complete a selection of the game's 52 missions depending on their faction. Only 36 missions are available in the international release, and a lock to the UPEO faction. These missions range from destroying squadrons of enemies to protecting a base from enemy fire. Player performance is graded from an A to D letter scale, which are logged in a chart on the title screen.

Electrosphere adds several new mechanics to the core Ace Combat gameplay. One of these is the ability to fly spacecraft, with one mission taking place above Earth in outer space. Players can watch instant replays of the mission's final moments at the end of each mission, as in Ace Combat 2. A limited number of planes and weapons can be selected for the first few missions, but only one can be used for the remaining half of the game. In the Japanese release, missions contain radio chatter from both the player's faction and opposing ones. In the international release, the player only receives radio chatter from their own faction. The radio chatter in the Japanese release contain avatar-like images of the characters. This is not present in the international release.The player can rotate their camera 360-degrees around their fighter in order to see what is behind them or get a better view of the level.

The Japanese release features additional content that is not present in the international releases. The most notable of these are the branching stage paths; depending on actions made by player input at certain sections of the game, the plot will change based on the outcome of those decision, leading to one of five possible endings. An in-game encyclopedia can be accessed, documenting information regarding the game's characters and technology. Anime-style video emails with voice overs can be accessed, played through a fictional email inbox. Obtaining all five endings will unlock Mission Simulator mode, which allows the player to replay any mission with any aircraft and weapon of their choice.

Ace Combat 3 is set in the series' fictional universe of Strangereal, where Earth has entirely different nations, geography, and history. Specifically, Ace Combat 3 is set in a partially-noncanonical cyberpunk near future rendition of Strangereal, in which the world's governments have been effectively superseded by multinational megacorporations that wield massive political, economic, and military strength, the two effective "superpowers" being General Resource Limited and Neucom Incorporated ("Neuwork" in the international versions). Both megacorporations, locked into a fierce power struggle in the continent of Usea, eventually declare direct corporate warfare against each other in 2040, prompting the Universal Peace Enforcement Organization (UPEO), an international peacekeeping force with dwindling influence, to respond to stop the Intercorporate War from worsening. A major part of the 2040 rendition of Strangereal is the "Electrosphere", a fictionalized version of the Internet; in the 2030s, advancements in technology made uploading one's consciousness to the Electrosphere possible, causing a rise in transhumanism as well as Ouroboros, a transhumanist terrorist group based out of the airship Sphyrna that believes humanity can ascend to a new plane of existence by uploading their consciousness to the Electrosphere.

In 2040, UPEO deploys their Special Armed Response Force (SARF), a fighter squadron led by Commander Park that includes Nemo, the player character, and Rena Hirose, a prodigous flying ace, to respond to incursions by Neucom in no-fly zones. Accusing UPEO of supporting General Resource, Neucom launches a preemptive strike on General Resource, initiating the Intercorporate War. To prepare for combat, Nemo undergoes aerial training from General Resource's top ace, Abyssal Dision. Impressed by Nemo's skills during a subsequent mission, Dision asks them to defect to General Resource. If Nemo stays with UPEO, they begin to fight General Resource, who are counterattacking Neucom. Nemo is later assigned to escort Gabriel William Clarkson, a UPEO delegate traveling to a conference to mediate a ceasefire, when Commander Park suddenly claims Clarkson is a Neucom spy and orders Nemo to shoot down Clarkson's plane; if Nemo spares the plane, Neucom offers Clarkson protection, and Nemo joins Neucom. If Nemo or Rena kills Clarkson, they remain with UPEO.

It is ultimately revealed that the conflict was orchestrated by Ouroboros, led by Dision, who had secretly been "sublimated" into the Electrosphere and made into an AI copy following a cover-up assassination attempt by General Resource aimed at destroying the mind-uploading technology he was testing. Commander Park is also revealed to be a member of Ouroboros who was using SARF to inflame the conflict. If Nemo never defects from UPEO, SARF breaks away from UPEO and Nemo defeats Park and Rena, who was brainwashed by Dision and forced to fly the advanced Night Raven prototype aircraft. Nemo fights and defeats Dision within the Electrosphere itself, ending the conflict for good. If Nemo chooses to join General Resource or Neucom instead, different potential endings can result, in which Nemo either defects to Ouroboros or remains with the corporation and ensures their victory; regardless, Nemo kills Dision in each ending.

After all five endings are completed, scientist Simon Orestes Cohen reveals Nemo is actually a combat AI within a simulation that Cohen has been training to eliminate Dision to avenge the death of someone he loved, fellow researcher Yoko Martha Inoue, who was killed in the same cover-up that killed Dision. Despite the non-sublimated Dision having also been a victim, Simon blamed her death on his presence, potentially due to his romantic affair with her. Satisfied in knowing that Nemo will defeat Dision in any possible scenario, Simon ends the simulation and releases Nemo into the real world.

Due to development constraints, the plot in the international versions of Ace Combat 3 was heavily pared down, with its characters, backstory, and multiple endings being removed. This version lacked voice acting and the majority of animated cutscenes present in the Japanese release, with the non-gameplay story elements being told through text slideshows between major missions.

Nemo, a human pilot flying for UPEO, deploys to fight off Neuwork's attacks on General Resource. It is eventually revealed that Ouroboros precipitated the conflict, led by a rogue AI developed by Neuwork codenamed "Aurora". Nemo fights and defeats Aurora inside the Electrosphere, ending the threat and the war itself.

Ace Combat 3: Electrosphere began development in 1998 following the critical and commercial success of Air Combat and Ace Combat 2. Directors Takuya Iwasaki and Atsushi and producer Takashi Fukawa led a team of other Namco employees during production, most of whom had worked on Ace Combat 2. The directors wanted the third entry to be far more ambitious than its predecessors in both content and presentation. The team focused primarily on making the storyline a key mechanic, which would change and affect the gameplay based on player progress and decision. Storylines in previous Ace Combat games were seen as unimportant and did not have a direct effect on the gameplay itself; this decision was to help make the story feel like an integral part of the game and to serve an actual purpose. Drama television shows and the game R4: Ridge Racer Type 4 (1998) served as inspiration for this idea.

During development, the team worked to make Electrosphere visually distinct from other combat flight simulators and create new technological breakthroughs. This led to the game's futuristic, science fiction setting and world, which was created through combining 1970s city designs and modern-day architecture. The developers used Ace Combat 2 as a basis for the game, leading to Electrosphere borrowing many of its ideas and concepts. Hardware limitations of the PlayStation and the team's limited skills made them skeptical of their vision and world being implemented. The console had difficulties rendering maps due to their size, which made the game difficult to program. Programmer Kenji Nakano created a workaround to this problem by rendering far-away objects with far fewer polygons than they were up-close, which took two months to implement. Cutscene animations were provided by Production I.G, featuring dark shadows and contrasting lines. To give the game the illusion of time passing, a day-to-night cycle was implemented. Graphic designer Minoru Sashida, who worked on the arcade game Techno Drive, designed the game's menu interface.

Tetsukazu Nakanishi, who had previously contributed tracks to Ace Combat 2, served as the lead composer and sound director of Electrosphere, which features a techno and electronica soundtrack. While previous games mostly featured melodic upbeat music akin to funk rock, the soundtrack features more emphasis on sound design than melodic elements, which Nakanishi felt fits the game's atmosphere and design. Other tracks in the game were composed by Koji Nakagawa, Kanako Kakino, Hiroshi Okubo, and Go Shiina, along with one contribution from Tomoko Tatsuta. Kakino incorporated elements of world music into her tracks to express nature and life, while sticking to the sound direction. Shiina extensively used an arpeggiator for his tracks, which he found very enjoyable to use. On May 27th, 2024, the game's 25th anniversary, a remastered release of Ace Combat 3's soundtrack was published on streaming platforms.

Namco announced Ace Combat 3: Electrosphere in August 1998. The company remained quiet about the game, making minimal comments during that year's Tokyo Game Show. The company broke the silence in November, opening up a website and showing conceptual artwork to video game publications. Only a single level and a select few aircraft were revealed. Namco announced it was slated for a release in the first half of 1999 in Japan. A small sample of video footage from the game was presented in a bonus disc shipped out with the Japanese release of Ridge Racer Type 4. Famitsu reported that the game was roughly 80% complete by January 1999. After months of secrecy, Namco demonstrated Electrosphere at the 1999 Tokyo Game Show, presented alongside World Stadium 3, Dragon Valor, and the Dreamcast conversion of Soulcalibur, taking up most of the Namco's booth. Ace Combat 3: Electrosphere was published on May 27, 1999 in Japan by Namco Inc.. Its size forced it to be split across two discs, each containing 26 missions for a total of 52 missions. Alongside a 26-page instruction manual, it contained a 30-page promotional booklet called the Ace Combat 3 Electrosphere - Portfolio Photosphere, which details the game's characters, aircraft, storyline, and other information regarding its fictional world. Also released was Ace Combat 3: Electrosphere Direct Audio with AppenDisc (a portmanteau of 'appendix' and 'disc') which contained the full game soundtrack as well as supplemental story footage and a 'deadcopy' save file which could be used to access the Mission Simulator mode. On December 7, 2000, it was re-released in Japan under the PlayStation the Best line of budget titles.

For the North American release, Namco Hometek Inc. removed all characters and considerably altered the original story-line, keeping only the inter-corporate conflict intact. Electrosphere was released in Europe on January 21, 2000, and in North America on March 7.

Frognation, a Japanese dubbing company, was contracted to assist in production of the localization process. They contacted Agness Kaku, a translator known for her work on games such as Metal Gear Solid 2: Sons of Liberty and D2, to help translate the game. She recalled doing a demo translation based on the original Japanese storyline, but because of funding being cut Namco America scrapped the translation entirely and chose to completely re-do the plot for overseas audiences; this included removing the multiple endings, branching story paths, and almost half of the missions. It was also slightly altered to fit onto a single disc. While an official reason was not given for the cut of funds, Kaku believes it was due to the game not selling as well as Namco hoped in Japan, which gave the American division little hope in it being successful either.

Namco presented the game at the 1999 Electronic Entertainment Expo (E3) exposition to mostly positive coverage. Before the funding was cut for the translation, Namco had already begun advertising the game's interconnected storyline. According to Kaku, when Namco stated that the American release would be heavily cut down and omit the original Japanese storyline, it was met with backlash from fans and publications, causing interest in the game to severely diminish when it was ready to ship.

A text-only fan translation covering most of one of the game's five routes was uploaded to GameFAQS in June 2000. In 2009, a fan-translation team called "Project NEMO" began work on a text-only English translation for all 52 missions, reaching completion in mid-2010. In December 2016, the same team published patches that translated the game's story. An update was published on January 1st, 2024.

In December 2021, a localization group called the "Load Word Team" translated the game in the Italian language. Later on May 27, 2023, the same team also completed translation to the English and Spanish languages.

The Japanese version received mostly positive reviews. Staff from Famitsu appreciated the game for its "overwhelming" graphics and deeper storyline, in addition to its realism. An Official Czech PlayStation Magazine reviewer had a similar response, enjoying its futuristic approach, realistic graphics, and refined gameplay. In an early preview, James Mielke of GameSpot commented that the game, while it was not as fun as Ace Combat 2, had the same ambitious design as R4: Ridge Racer Type 4, with personality-driven cutscenes, sleek fighter craft designs, and detailed graphics. Edge staff members highlighted its branching storyline, stating that it makes the game more involving and rewarding than its predecessors.

By a drastic comparison, reviews for the North American and European releases were met with a much more mixed response. Because international versions had a significantly lower amount of content than in the Japanese version, reviewers showed confusion and disappointment towards the lack of missions and a proper storyline for diminishing the game as a whole. Mielke presented a radically different response to Electrosphere from his preview, writing that its removal of content from the Japanese version and linear approach made the game feel inferior to its predecessor Ace Combat 2. NextGen's Eric Bratcher agreed that without its branching level system and additional campaign, it felt boring to play and not nearly as refined as earlier Ace Combat games. Mandip Sandhu of The Electric Playground showed disappointment towards the plot and bland cutscenes for creating a story that had little to no significance over the game itself. Dean Evans of Official UK PlayStation Magazine said that it felt more like a PC flight simulator than an Ace Combat game, mockingly writing: "Namco prove that yes, it is possible to recreate PC-style flight sim graphics on the PlayStation. But, unfortunately, they forgot to include a game to go with them." Not all reviewers expressed criticism over the game; Sam Bishop of IGN and Dr. Zombie of GamePro both praised the gameplay for being solid and energetic, with Bishop in particular commenting that it "delivers the same action-packed air combat experience that you've come to expect from the series, and does it with an unmatched style and flair that's never over the top". Jeuxvideo.com's Kornifex said that it had the same refinement as Ace Combat 2, with a large selection of fighters and varied missions.

Critics agreed that Electrosphere posed "gorgeous" graphics with plenty of detail. Bishop said it had an amazing sense of detail and proved to be one of the game's strong points. Dr. Zombie and Mielke both agreed, with the former author in particular saying that it had a unique blend of realistic and arcade-esque graphics. Mielke also liked the game's high production values. Sandhu complemented its visuals for their high amount of detail, as did Kornifex and Evans. Reviewers also praised the game's control scheme for being responsive and easy to use, with Dr. Zombie specifically pointing out its realism to actual aircraft. Kornifex also praised the game's usage of the PlayStation DualShock controller to great effect, namely with its rumble feature and smoothness. Electrosphere's soundtrack, usage of instant replays, and considerable lack of slowdown were also the subject of praise. Although Bratcher praised the graphical style and gameplay mechanics, he felt it ultimately fell short compared to its predecessors, writing that the game "has too many arcade elements to be a serious flight sim. Unfortunately, it's also too boring to be a great arcade-style dogfighter." In another GamePro review, however, Lamchop said that the game "is not for the gamer who just wants to jump in and shoot things out of the sky. On the other hand, if you want to take a shot at handling a multition aircraft, this may be a flight booked for you."

Commercially, the game under-performed, and was not as big of a hit as Namco hoped it would be. It was commercially unsuccessful in North America and pulled fewer units than previous entries. By 2008, Electrosphere had shipped 1.164 million units worldwide, barely surpassing Ace Combat 2's 1.092 million worldwide shipment.

The game won the award for "Shooter" in both Editors' Choice and Readers' Choice at IGN's Best of 2000 Awards.

Ace Combat 3 has received better feedback in retrospect, with critics identifying its ambitious design and story. In celebration of the game's 20th anniversary in 2019, Game*Spark retrospectively compared the complex storyline of Electrosphere to that of Final Fantasy VII and Ridge Racer Type 4, praising its branching path system for having a meaningful, interesting impact on the plot as a whole. They also liked the game's futuristic atmosphere and theme, a drastic departure from other Ace Combat games. Game*Spark further stated that Electrosphere was one of the best and most unique games in the series, showing disappointment towards the lack of a modern digital release on platforms such as PlayStation Network.

Sebastiano Pezzile, a writer for Player.it, reviewed the game in 2019 to commemorate the launch of Ace Combat 7: Skies Unknown. He compared its story and visual style to that of Neon Genesis Evangelion and Ghost in the Shell, enjoying its larger storyline for being far darker than its predecessors. While Pazille praised its Wipeout-influenced soundtrack, he was critical of the international version for being inferior to Air Combat and Ace Combat 2 from a content standpoint. Writing for GameRevolution, Tyler Treese also expressed his disappointment in the game's international release, believing it made for one of the worst attempts at video game localization.

• Official website (in Japanese)
• Ace Combat 3: Electrosphere at MobyGames