Astro Boy: Omega Factor is a video game for the Game Boy Advance handheld video game console, developed by Treasure and Hitmaker. It stars Astro in a plot lifted from several Astro Boy iterations. The action takes place as a horizontally scrolling shooter, with Astro Boy facing an onslaught of robotic enemies using the various weaponry at his disposal.
Dr. O'Shay is then shown introducing himself to Astro Boy. He teaches him his controls and the Omega Factor, a part of him that tells him of others, boosting his powers. Suddenly, the doctor's assistant, Wato, is kidnapped by robots. Astro chases them through Metro City, when he finally catches up to Wato, she reveals that the cause of the out-of-control robots was the Magnemite. After Astro Boy defeats it, Atlas revealed himself as well as being the cause of the Magnemite fighting him.
Soon afterwards, Inspector Tawashi and Zoran are introduced, the former tells Astro of aircrafts burning over the Pacific Ocean. Astro finds the Artificial Sun, defeats it, and follows it to Cruciform Island. Upon landing, he meets Pook who claims to know Astro. He also meets the Amazing Three, Big X, and Wally whom he helps open a door for. Fighting his way through V3 robots, Astro finds Kinsankaku and Skunk, who have been using Pook to steal riches. Pook is forced to fight Astro with the deal of being freed, Wally and the other heroes get the entire island surrounded to arrest the Kinsankaku. Then someone took over Mr. Tokugawa's moon base and is holding his son, Daichi, hostage. Astro is sent there, but when he finds Daichi, he reveals that he is Atlas, Daichi's replacement who had died. Their battle is interrupted when Atlas gets a headache due to the sudden appearance of a woman in a capsule.
Astro gets invited to visit the newly elected president of Antarctica, Rag. He meets him, the international councilor, Duke Red, and his "daughter", Nuka. Astro saves her from an attack of the Black Looks and takes a liking to her. Then Astro follows the leader, only to find out that it was a fake so that he'd be far away allowing the Carabs to be sent to the palace to destroy it. Fortunately, Astro makes it back and destroys the Carabs just in time. The inauguration ceremony gets interrupted by the real Black Looks leader, Lord Deadcross, who believes humans are superior to robots. He sends Black Looks against Astro and tries to escape on the Marine Express. When Astro catches up to him, he reveals himself to be Rock, the original human that Rag was created in the image of. Rag was used as a promoter, but he soon turned and ran against Rock. Suddenly, the Marine Express is hit with magic, it gets transported thirty thousand years into the past to the continent of Mu. Its ruler, Sharaku, tries to make them their slaves, but they are saved by Pook who takes them to Princess Sapphire. Astro heads towards and defeats Sharaku, but he is unfazed due to a potion he has. Three months later, they found a way to travel back to the future, though Rock stays behind hoping to prevent Mu from sinking with Sapphire.
Unfortunately, when they get back, they find that humans and robots have been at war for five years. One robot named Shadow has Zoran and the world's strongest robots, North, Denkou, Brontus, Epsilon, and Pluto, as forces in Antarctica. Astro refuses to join his cause and defeats the strongest robots. Shadow reveals that he is Sharaku having traveled through time using the potion to rule the world. He also shows him the Death Mask, a "goddess" that will exterminate all robots using Omotanium as punishment for decimating the planet. While Sharaku leaves to find another timeline where Death Mask won't get in the way, Astro is killed.
However, he is saved by the Phoenix, who gives him the power of time travel so he can make a better future. Transcending through time, Astro Boy witnesses two children watching a rocket launch before one of them will stay in a hospital, their names are Prime Rose and Daichi! During another tutorial, O'Shay reveals to Astro why Dr. Tenma created him and where he used to live. Aside from Astro's new choices, there are other changes in the timeline due to the travelling. For example, a man named Drake, who wishes to destroy all robots, won against Duke Red for the new international councilor. After the events on Cruciform Island, Astro is visited by Nuka who wished to see him before she "left", she knew about the Phoenix!
In the new timeline, Rag is assassinated, and Rock is elected president. When Astro arrived, the robots attack Antarctica for revenge. Their leader is Blue Knight, who wishes to build Robotania, he is the one who sends the Carabs to the palace this time. During Rock's inauguration speech, Wally presents Deadcross' mask as evidence against Rag's assassination. Rock is forced to escape on the Marine Express and is again traveled to Mu with Astro and Wally. During his time in Mu, Astro frees Unico who allows him to connect with Dr. Tenma at their old house. He also learns from Don Dracula that Sharaku's potion allowed his soul to be placed in a coffin at Fire Vase Island, that's where Wato and Boon were excavating in the future. Astro tries to warn Boon, but Sharaku jumps out of the ruins and escapes. Three months after Mu, Shadow is replaced by Blue Knight and Astro saves Tawashi, Skunk, Kinsankaku and Mr. Tokugawa while fighting the strongest robots. Kinsankaku reveals that he found Pook after a voice in his head told him to dig under Cruciform Island. Mr. Tokugawa reveals that he created Death Mask under Duke Red's orders! Blue Knight is surprised when he finds that Astro only disabled Pluto and the other robots, Zoran is left with Pluto while Astro time travels again.
Astro finds Duke Red in a building hidden in the icebergs, he reveals that Death Mask was created out of fear that robots would turn on humans and exterminate them first. He also reveals that Nuka was made into Death Mask! At that moment, Blue Knight suddenly appears wanting the location of Death Mask. He challenges Astro to a duel and the latter is victorious. Blue Knight is revealed to be Rag who was repaired by Tenma, he informs Astro that Alejo may know something about Drake. Alejo reveals that his daughter was apparently killed by a robot and upon questioning Drake, he confirmed it. It happened in the hospital; he even had a video as proof. Her name was Prime Rose, she had a disease that could only be cured by Dr. Black Jack, but no one knows where he is. She was the same girl in the capsule on the moon with Atlas, who mentions Kennedy, an old friend of his who found the doctor. When Astro came to the doctor's house, Ham Egg refused to let him see the doctor, he's had Skunk kidnap his "daughter", Pinoko. Astro manages to rescue her with the help of Rainbow Parakeet, Ham Egg reveals that he's been bribed to prevent Black Jack from working. Astro realizes that Sharaku masterminded the entire game, he gave Kennedy amnesia, but it wore off after what happened on Fire Vase Island. Black Jack is taken to the moon to successfully operate on Prime Rose, who stops Drake from killing Duke Red and himself. Mr. Tokugawa reveals that Daichi took Prime Rose to the moon to fulfill her wish in seeing it, but he died after being exposed to the Omotanium for Death Mask's construction there. Drake tells Atlas to take care of Prime Rose while Dr. Tenma gives him a part of his original human body.
Astro has a talk with Nuka inadvertently revealing Death Mask's location to Sharaku. He sends immortal versions of the Magnemite, Artificial Sun and Carabs to fight Astro but Pluto, Atlas and Blue Knight hold them off. After another fight with Sharaku, he reveals that Omotanium is also a living substance of Mu's treasure. He has Pook, or rather Pick, use it to transform into Garon whom Astro defeats. But the Omotanium falls into the sun, so Astro Boy throws a part of Nuka and himself into it to prevent a huge explosion. The Phoenix revives both of them and allows them to return home, Tenma hopes Astro will become grow for mankind like the star he had once told Tobio about.
A couple minutes after the "The End" screen is shown, Sharaku is seen hiding on Fire Vase Island with Pook. He was hoping to bring Garon back even though Pook was against this. However, Wato arrives and covers Sharaku's third eye with a bandage sealing his psy powers and evil personality.
Differences from Other Sources
- Wato is Professor O'Shay's assistant instead of Yuko Kisaragi and Momo.
- Atlas was the cause of the Magnamite, spelt as "Magnemite" (no the) in this game, going out-of-control. In Power Up!, it happened by itself due to a power overload caused by Astro Boy's awakening, no other robots went out-of-control either.
- Uran is named "Zoran", and although she appears in the game, Astro's parents, Cobalt, and Chiitan do not.
- Pook has the appearance, and later true identity, of Pick, the heart of Garon. He transforms by disappearing and reappearing in a flash of light. One of his transformations is "Kimba the White Lion", whose role is taken from the movie, Undersea Super Train: Marine Express.
- The plots with the Artificial Sun and Pook stealing were happening at the same time. In the original manga/anime, these were two separate chapters/episodes.
- Instead of Hamegg, Skunk worked with Kinsankaku and used Pook to steal (similar to how he used Denkou). Due to Pook really being Pick, Dr. Tozawa is absent from the game.
- Similar to "The Man-Made Solar Sphere", Sherlock Holmspun from the The Artificial Sun is merged with Rainbow Parakeet, whose last name is spelt as "Homespun".
- The Roboids that appear in the game are actually the robots from "Duke Goblin".
- The Marine Express travels from Metro City (or "Metropia") to Antarctica instead of from Los Angeles, California to Tokyo, Japan like in Undersea Super Train: Marine Express.
- Rag is redesigned to resemble Rock and he is the president of Antarctica, the location of the Black Looks, instead of Guravia. His secretary, Half'n, is absent, Duke Red and Nuka seem to take his place.
- While most incarnations portray Duke Red as a villain, he is a genuinely nice character in this game. Except the fact that he ordered Death Mask to be made, but even then, his intentions were somewhat justified.
- The Karabusu from The 100 Million Year Old Crime is renamed the "Carabs". Although it stills functions as a tank and looks like a dung beetle, its transforming ability is omitted and turning it into a bomb was made for this game. Also, Parma, her father, and the five boys that were also present in the story are absent.
- Lord Deadcross, Rock, and Black Lux are merged into a single character.
- Rock in particular is based on the version from Undersea Super Train: Marine Express, except here his hair is black instead of brown.
- Originally, Deadcross' minions looked like him, the same for Black Lux's gang, though Lux had a long nose. Here, the Black Looks are redesigned to have their hats casting shadows over their faces instead of having them wear masks resembling the controversial blackface makeup.
- Although several other Tezuka characters from Undersea Super Train: Marine Express appear in the game, only Astro, Wally and Rock ride on the titular train and are transported to Mu. Also in the movie, Astro (named "Adam") sacrificed himself to defeat Sharaku by blowing up the Marine Express, he was built as a bomb for it.
- Sharaku's role in the game, as well as Don Dracula and Princess Sapphire's, is mainly based on his role in Undersea Super Train: Marine Express. However, the design of his third eye, as well as the fact that his powers get sealed when its covered up, and his relationship with Wato comes from his own series.
- Astro Boy is the one who fights the world's strongest robots instead of Pluto, who instead is the final opponent. None of the robots are destroyed, just disabled.
- Chochi Chochi Ababa the Third, Dr. Abullah, Gerhart, Hercules, Bora, Harley, Delta, and Acheron are all absent. Although Bora is mentioned in the character profiles, his name is misspelt as "Boraa".
- Denkou did not take part in any version of the story. Though the fact that he drops bomb belts during his battle and that Skunk is released during Rebirth after Denkou is defeated are homages to Electro, the original story, and its adaptations.
- Brontus has the appearance of Montblanc, but the attacks of Brando.
- Epsilon is mainly based on her 2003 anime counterpart, but she is referred to as a male. Plus, one attack is a health draining one involving beams of light, similar to her original counterpart.
- Though a separate character in the 2003 anime, Shadow in this game is merely a disguise of Sharaku.
- Although Blue Knight wanted to build Robotonia in Antartica like in the 2003 anime, in the original manga Robotonia was located on a plain known as Kumo No Taira in the Japan Alps.
- Niki is named "Nuka" in the game.; She is made into the Death Mask satellite weapon from the Prime Rose manga; however, she is also a humanoid control system for a weapon of mass destruction similar to Bem. She also has similarities to Mitchy and/or Tima from Metropolis having been created on Duke Red's orders using the power of Omotanium and plugged into a machine that can affect the sun. At the end of the game, she is brought back to life and wasn't turned into anything else. In Astro's First Love, she is dismantled, and Astro replaces his legs with hers.
- Rag becomes Blue Knight and Blue Bon, Tonto, Maria, Dr. Los, and Count Burg are absent. Although Burg is mentioned in the character profiles, he is named "Lord Bulg".
- It is revealed that Dr. Tenma just left Astro so he could grow stronger. In the original manga, as well as several adaptations, he sold him to a circus because he couldn't grow up.
- Daichi died from Omotanium exposure after taking Prime Rose to the moon. In the 2003 anime series, he was caught in a fatal space shuttle accident.
- Astro is able to destroy Garon in this game. But in Astro vs. Garon, he couldn't (possibly due to Pick's absence), instead he tricked him into flying into outer space.
- Astro flying into the sun is similar to what happened in The Greatest Adventure on Earth (as well as Bem's sacrifice). However, he did it alone that time, and it was locust aliens that saved him instead of the Phoenix.
- The game was originally called "Astro Boy Tetsuwan Atom: Heart no Himitsu" (Astro Boy Tetsuwan Atom: The Heart's Secret).
- The Western title is misleading, since Omega Factor is actually a hazardous device which gives an evil mind to a robot or even deprive it from its mind.
- Kokoro was renamed to Omega Factor, despite the fact Omega Factor is the opposite in the series actual canon.
- The pictures of each stage resemble the covers of Osamu Tezuka Manga Complete Works edition manga books.
- The V3 robots that appear on Cruciform Island are from the Big X manga.
- Stage 4 is still named "Lord Deadcross" in Rebirth as well as him appearing on the cover, despite the fact that Rock doesn't appear as him at all. Similarly, Shadow still appears on the cover of Stage 7 despite being replaced by Blue Knight.
- Stage 6 is named after the "Lost World", one of Tezuka's manga. But in spite of this, the stage is based on the Mu part of Undersea Super Train: Marine Express.
- The character profiles incorrectly state that Nuka was blown up in front of Astro in the 1980's anime instead of dismantled.
- Jetter Mars, Fumoon, Magma, Hecate, and Abercrombie also appear in the game. Abercrombie is automatically entered into the Omega Factor and in Rebirth he is required to be encountered again to find Duke Red and fight Blue Knight. Ambassador Magma is required in order to complete what happens on Fire Vase Island. The rest are really optional (along with Unico and Dr. Tenma), but Hecate foreshadows Prime Rose and Daichi's relationship.
- Even though many of Osamu Tezuka's characters appear in the game, there still some quite notable who are absent. Aside from the ones mentioned above, these include Chief Nakamura, Dr. Saruta, Marvelous Melmo, Sasaki Kojiro, Hyoutan-tsugi, Spider, and the avatar of Osamu Tezuka himself.
- The gameplay of the Nintendo DS game based on the American CGI film was inspired by this game.