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All of you ungrateful humans, who took everything away from me, will feel my loss and despair!

— Gerald Robotnik, Sonic Adventure 2

Professor Gerald Robotnik[2] (プロフェッサー・ジェラルド・ロボトニック[3] Professā Jerarudo Robotonikku?) is a character that appears in the Sonic the Hedgehog series. He was a human scientist and the grandfather of Maria Robotnik and Dr. Eggman. A world-renowned scientist who is widely acknowledged as one of the greatest scientific minds of all time, Gerald was responsible for several groundbreaking creations, including his greatest achievement, Shadow the Hedgehog, making him a modern day scientific Da Vinci.[1]

Over fifty years ago, Gerald was asked by the President of the United Federation to lead Project Shadow, a medical program for inventing immortality, which he accepted in hopes of finding a cure for a fatal illness afflicting Maria. Eventually, Gerald managed to create Shadow the Hedgehog, though not without drastic measures; he was taken into custody by the military when his work was deemed too dangerous. When learning that Maria had been killed by the military, Gerald slipped into madness and spent his last days plotting revenge against humanity.


Gerald Robotnik bore a distinct resemblance to his grandson. He had broad and elevated shoulders, a round, almost egg-shaped, torso (though not with as large a girth as Eggman), slightly over-proportioned arms and legs, and large hands and feet. He was also bald with a dome-shaped head, a long and large nose, and low-set small ears. Like Eggman, he also had an oversized mustache, except his was whitish-gray, more voluminous and smooth. He was also not very tall of stature, only being about half a head taller than Maria.

Gerald's general attire consisted of a red turtleneck sweater and a white lab coat with black buttons. He also wore blue pince-nez glasses which had a distinct ripple-like pattern on them. In Sonic Adventure 2 he was shown wearing white pants, while in Shadow the Hedgehog he is seen wearing brown pants and blue slippers.

In Sonic Adventure 2 and its remaster, Gerald's design was slightly different. In these games he was skinnier, had more normal body proportions, his head was slightly pointier, and his mustache was more ragged. His glasses also had no ripple pattern.



It has been implied that Gerald comes from a long line of brilliant scientists.[4] The greatest mind of his time, Gerald, who believed his purpose in life was to bring the people of the world happiness and hope through science, set out to help the world by dedicating his life's work to the people of earth.[5][6] During his career, Gerald accomplished many great things, one of them being the Space Colony ARK, the world's first space colony which he designed.[2] Other accomplishments included discovering and researching an interdimensional beast called the Ifrit, which he wrote several files about,[7] and being the first to propose the existence of the Fourth Great Civilization.[8]

Eventually, Gerald had a granddaughter named Maria Robotnik, whom he became extremely fond of.[9] Gerald would come to live and work with Maria onboard the Space Colony ARK, where he took care of his granddaughter, who needed constant attention because she suffered from Neuro-Immune Deficiency Syndrome, an incurable and inevitably fatal disease.[1][10]

Project Shadow

Over fifty years prior to Shadow the Hedgehog, Gerald, at the height of his career, got a letter from the then-President of the United Federation who requested his help with a medical project named "Project Shadow", a medical program meant to research immortality and develop an "immortality formula."[10][11] Initially, Gerald stubbornly refused this request, believing they were crossing the limits of man and that this research could be used for war efforts. However, upon realizing that the immortality research could be used to develop a cure for Maria's illness, Gerald eventually accepted the President's request and agreed to lead the project on the Space Colony ARK in secrecy.[10]

Initially, Gerald's fellow researchers doubted the project's success, even with Gerald's brilliant mind on their side. In the first stages of Project Shadow, Gerald researched the Chaos Emeralds, which resulted in the creation of the Chaos Drives, during tests to apply chaos energy to living beings. When those tests proved successful, Gerald and his colleagues moved on to creating an immortal creature dubbed the "ultimate life form".[10] During the development however, Gerald needed help with his research. He thus contacted Black Doom, the leader of the Black Arms, an extraterrestrial race of aliens from the Black Comet, a celestial body that was passing by the earth at the time, and made a deal: Black Doom would help Gerald with his work, even providing his blood as DNA for the project, and in return, Gerald would have his creation deliver the seven Chaos Emeralds to Black Doom in fifty years, which would be when the Black Comet made its return to earth.[12][13] However, Gerald eventually discovered Black Doom's plans to use the Chaos Emeralds to devour the human race. Realizing his mistake, Gerald secretly plotted against Black Doom by developing the Eclipse Cannon, a weapon capable of destroying the Black Comet, and the Black Arms with it, upon their return.[12][14]

Gerald and his colleagues eventually produced the prototype of the ultimate life form, dubbed the Biolizard. While it lived up to many of their expectations as it grew, the creature proved too flawed.[10] In addition to a bestial and unruly nature, weak limbs and reliance on machinery for survival, Gerald noticed the Biolizard grew too fast and requested that the control part on its vital organs was reinforced.[15] Despite these results, Gerald moved on with the project. Using the DNA of Black Doom, Gerald created a new version of the Biolizard, but with another physique,[10] dubbed "Shadow the Hedgehog." Unwilling to weaponize Shadow though, Gerald gave him a "heart" and "soul" similar to Maria's in hopes that he would not become a tool of mass-destruction.[6] He also secretly changed him to be the savior of mankind by helping stop the Black Arms upon their return, believing that only someone with their powers could stop them.[16]

During Project Shadow, Gerald would create more artificial creatures on behalf of GUN who wanted their own "Chaos monsters". His experiments eventually led to the creation of the experimental Artificial Chaos units, synthetic life-forms based on the god of an ancient culture.[17][18][19]

The Gizoid

In the meantime, Gerald uncovered an ancient robot called the Gizoid from a warehouse. Believing it was made by an ancient civilization, Gerald experimented on it with Chaos Emeralds and accidentally activated it. By researching papers related to the Gizoid and the Chaos Emeralds, and later an ancient stone tablet which he had discovered, Gerald theorized this robot was what caused the destruction of the Fourth Great Civilization. His further research and observations also revealed the Gizoid could mimic combat abilities and weapons, and that it possessed vast amount of data on melee combat and weapons of its age, data that which crashed Gerald's most advanced computers when he tried scanning it. Theorizing the Gizoid's full potential should it be fully restored, Gerald realized he had uncovered a horrible weapon.[20]

As Gerald continued to research the Gizoid, he discovered that the Gizoid would swear loyalty to those with great power by establishing a "Link" with them. To keep the Gizoid under his control and from being used for evil, Gerald successfully made a Link with it by demonstrating his model weapon collection to it. However, in fear of someone with evil intentions forming a Link with the Gizoid, Gerald researched how to re-establish a Link with the Gizoid should it be lost.[21]

Government and Shadow

When Shadow neared his completion, Gerald learned the government had become uneasy about the outcome of Project Shadow following his contact with the Black Arms. With Gerald's invention beginning to be perceived as potentially dangerous to humanity, the government considered cutting funding.[22] Unwilling to let his study get ceased now that he was so close to finding a cure for Maria, Gerald made a big risk and offered the Gizoid as a bribe to the government to keep Project Shadow going.[23] While Gerald ordered the Gizoid not to absorb dangerous technologies, other researchers tried to form a new Link with the Gizoid by demonstrating great power. Eventually, Gerald's fears were confirmed when the Gizoid went on a rampage that destroyed most of the ARK before it was subdued. Deeming the Gizoid too dangerous, Gerald tried to destroy its core but failed due to its advanced technology. Instead, he planted a code-based "heart" and "soul" based on Maria's in the Gizoid that would grant it free will and emotions. Gerald hoped that these qualities would prevent the Gizoid from becoming a weapon of mass-destruction.[6][24] In case the Gizoid went out of control however, Gerald implanted a final program in it that would prompt it to self-destruct should that time come.[25]

Gerald and Black Doom overseeing Shadow's awakening, from Shadow the Hedgehog.

Eventually, Gerald's years of research bore fruit when Shadow was finally created,[1] with both him and Black Doom overseeing Shadow's awakening. Shadow proved to be everything Gerald had hoped for, possessing both immortality, high intelligence, own identity, and independence. In addition, Shadow became very close to the residents of the ARK, especially Gerald's granddaughter, Maria. Learning however that the government planned to cease his research after deeming Shadow a threat to mankind,[12] Gerald prepared a contingency video for Shadow. In it, Gerald discussed the government's plans to close Project Shadow, while also explaining how Shadow was meant to stop the Black Arms when the Black Comet returned in fifty years.[12][14]

During the time Shadow was raised, Gerald unintentionally had an accident with his Artificial Chaos which caused them to run loose. Gerald himself dictated this mistake to his old age.[26] Fortunately, Shadow and GUN ensured the situation was brought under control.


Gerald's suspicions were confirmed when GUN attacked the Space Colony ARK sometime after the completion of Project Shadow to eliminate everything and everyone related to the project and shut the ARK down. During the attack, Gerald put his finishing touches on Shadow. When GUN's Special Forces rushed into the ARK's laboratory, Gerald entrusted Shadow to Maria and left them to flee in the ARK's escape pods. He later made sure that one escape capsule was ejected towards earth, and Gerald assumed that Maria and Shadow had escaped to safety.[1][10]

Gerald was eventually captured under the guise of disappearing under mysterious circumstances and taken to Prison Island where he was forced to continue his experiments under military control.[1][2] Meanwhile, when it was released to the public that the ARK was shut down due to an accident, Gerald was blamed for causing it.[10] When the military later found Shadow, who got placed in suspended animation, and brought him to Prison Island for Gerald to continue his research,[1] Gerald saw Maria among the list of casualties when the ARK was shut down and was grief-stricken. Unable to cope with the loss of his granddaughter, Gerald began to lose control of his mind as he could only think of avenging Maria and ending everything, something which terrified him.[9] As a result, he would unwillingly scribble calculations he made for a doomsday plan in his cell. During the period where he still had control over his mind, Gerald got a hold of the Gizoid again and use this opportunity to make Maria's dying words the keywords that would activate the Gizoid's free-willed emotions-based AI once all seven Chaos Emeralds were inserted into it.[27]

Gerald in his last moments, from Sonic Adventure 2.

In the end, Gerald lost his grip on reality and went insane, devoting himself to avenging Maria by destroying humanity.[9] While it was thought that he was continuing his research with Shadow,[1] Gerald secretly created a program that would cause the Space Colony ARK to fall to earth and destroy the planet once the seven Chaos Emeralds were placed into the Eclipse Cannon, and set the Biolizard up as well to ensure this. Gerald also brainwashed Shadow,[1] altering his memories of what Maria wanted of him as her final wish so that he would carry out his plan once he was awoken. Gerald then left a note behind in his diary that encouraged the reader to release Shadow if they wanted to cause global destruction.[9] Soon after, Gerald was incarcerated on Prison Island by the military when they began to fear of how he could retaliate.[1] Just before he was executed, Gerald's last action was leaving behind a recording where he condemned the ungrateful world to destruction for the fate of Maria by giving his estimate for how long it would take for the ARK to collide with earth.


Because of the tragic deaths Gerald's research indirectly caused and the potential dangers to humanity his discoveries posed, many would view Gerald with contempt. The Commander himself came to consider Gerald insane and held a life-long grudge against him for creating Shadow, which indirectly led to the death of Maria. Many of Gerald's late creations, research and, discoveries which would form his legacy were either sealed or placed under tight security due to their potential for calamity. Gerald's Chaos Drives continued to be used by GUN as power sources for their mechs. Prior to his execution, he also conducted several mathematical equations within his prison cell, which would later be found by Amy Rose.[28]

Despite Gerald's bad reputation, Gerald's grandson Dr. Eggman looked up to him and admired him for the great things he accomplished. This inspired him to become a scientist, though Eggman would use his intellect to try achieving world domination. Gerald's forbidden research would also be uncovered over time by his descendants, namely Dr. Eggman and Dr. Eggman Nega, who would use it for their own nefarious purposes.

Sonic Adventure 2

Gerald appearing on the ARK's computer screen after Eggman activated his doomsday program, from Sonic Adventure 2.

In Sonic Adventure 2, Shadow was awakened by Dr. Eggman after the latter found his grandfather's diary. After awakening, Shadow would unknowingly carry out Gerald's plan to destroy the world, believing that he was fulfilling Maria's (false) wish for revenge. Shadow subsequently deceived Eggman into activating Gerald's program that put the Space Colony ARK on a collision course with the earth, causing a recording of Gerald condemning the world to destruction in his final moments to be played across the world. However, Shadow would eventually remember the real promise he made to Maria, which made him seek to stop the ARK's collision with the planet. Together with Sonic the Hedgehog, they stopped the ARK and foiled Gerald's revenge plot. Eggman, in turn, began to doubt his grandfather, seeing as he wished to destroy the world in the end.

Sonic Battle

In Sonic Battle, Dr. Eggman recovered the same Gizoid Gerald found, thus putting the world in danger. In an effort to keep the Gizoid from becoming a weapon of mass-destruction, Shadow and Rouge discovered from Gerald's notes that they could reset the Gizoid and turn it into an ordinary robot with the program Gerald had inserted into it if they gave it the seven Chaos Emeralds and the keywords "Bring hope to humanity." After the duo accomplished this though, Eggman managed to lure the Gizoid to the Death Egg. However, his attempt to make it forge a Link with him backfired when it caused the Gizoid to attempt to destroy the earth with the Final Egg Blaster. In the end, he was stopped by Sonic. Since the Gizoid had grown too powerful as well, it enacted Gerald's final program, which was making itself self-destruct.

Shadow the Hedgehog

Gerald's recording being played worldwide, from Shadow the Hedgehog.

In Shadow the Hedgehog, the Black Arms returned to invade the earth and collect the Chaos Emeralds Gerald had promised them. Shadow, who was suffering from amnesia following the Space Colony ARK incident, agreed to help Black Doom collect the Chaos Emeralds in hopes that the alien would reveal the secrets of his past to him, which threw a wrench into Gerald's original plans. However, when Black Doom was on the cusp of total victory, Team Chaotix managed to activate one of Gerald's recordings onboard the Space Colony ARK, which was broadcasted world-wide for everyone to see, including the President, the Commander, Black Doom and Shadow. In the video, Gerald explained the freezing of Project Shadow, his plan to destroy the Black Comet with the Eclipse Cannon, and that Shadow was the only one who could defeat the Black Arms. This recording gave Shadow the resolve to stand against Black Doom and ultimately destroy him. After the Black Comet was destroyed with the Eclipse Cannon, the President and the Commander decided to pay homage to Gerald by working towards a brighter future. On the other hand, Dr. Eggman realized that his grandfather was more brilliant that he initially saw.

Sonic Rivals 2

In Sonic Rivals 2, Dr. Eggman Nega discovered the Gerald's notes about the Ifrit, which he then sought to release upon the world from its dimension. However, his attempt was foiled by various heroes, villains, and anti-heroes.

Other game appearances

Sonic Rivals

Card 058 (Sonic Rivals).png

In Sonic Rivals, Gerald makes an appearance on the 58th collectible card in the game.

Super Smash Bros. series

Super Smash Bros. Brawl

In Super Smash Bros. Brawl, Gerald is mentioned in the description for Shadow the Hedgehog's Trophy.

Super Smash Bros. for Nintendo 3DS and Wii U

In Super Smash Bros. for Nintendo 3DS and Wii U, Gerald is mentioned in the description for Shadow the Hedgehog's Trophy.

Sonic Chronicles: The Dark Brotherhood

In Sonic Chronicles: The Dark Brotherhood, one of Gerald's quotes from his book "The Fourth Great Civilization" is shown before the start of the game.

"One thing remains a certainty: At the height of their glory, even they could not have foreseen their fate, or the speed with which it was delivered."

Sonic Generations

In the console/PC version of the game, Gemerald is mentioned in Shadow the Hedgehog's character bio in the Collection Room.

Sonic Runners

In Sonic Runners, Gerald is mentioned in Shadow the Hedgehog's character profile.


Before his descent into madness, Gerald was a good man and a profound humanitarian, the very much opposite of his psychotic grandson Eggman. He was devoted to using his intellect to help mankind and bring them happiness and hope through the power of science, which he believed was the reason for his existence.[5][6] While he was much more serious about his work than Eggman,[1] Gerald remained a caring person towards his family. As old age began to catch up to him, though, Gerald would become more forgetful.[26]

Gerald was a man of strong ethical standards, refusing to use his genius for the wrong reasons. He initially refused to lead Project Shadow since he thought obtaining immortality was against nature and because he had no interest in aiding with war.[6][10] That said, he was not above breaking his ethics for certain reasons, like when being forced by the higher-ups or when he thought it was for the greater good, such as joining Project Shadow or handing over the dangerous Emerl just to find a cure for his dying granddaughter. Even when in such situations, however, Gerald went out of his way to make sure his research would have the potential for good as well, like how he gave both Shadow and Emerl genuine feelings and planned to share Shadow with the world to help mankind. He also held the strong belief that power born from the desire to protect rather than the desire to conquer would make all conflicts cease to exist.[29] Also, although Gerald was willing to make a deal with Black Doom in order to complete Project Shadow, upon realizing the alien's ulterior motives of conquering earth, Gerald set to retaliate against his benefactor despite promising to give the seven Chaos Emeralds to him, showing that Gerald is willing to undermine a deal for the sake of protecting earth and humanity.[12][14]

When Maria was killed, Gerald went through a profound change, as he was consumed by grief and slowly went insane. He eventually became a rage-filled psychopath, developing a deep hatred for humanity who he blamed for Maria's death, and grew obsessed with revenge by committing global genocide. To this end, he turned Shadow and the Eclipse Cannon — both of which he originally conceived to defend earth from the Black Arms — into weapons of mass destruction, completely in contrast of his original humanitarian and peaceful ideals. Even in his last moments, all Gerald had to express was his contempt for humanity, and he died a broken man.

Powers and abilities

Gerald was an extremely knowledgeable and gifted scientist with an incredible intellect, even when compared to present-day geniuses. As a testament to his intelligence, he is regarded as both one of the most brilliant minds ever and the most gifted researcher of all time.[2][30]

Gerald possessed many talents, having mastered several areas of study, including architecture, science, astrology and foremost biology, along with genetics to astrophysics to robotics.[1] He was the one who designed the world's first bernal sphere space colony, the Space Colony ARK, and developed incredible devices and machinery such the Eclipse Cannon, which has the power to destroy planets and pierce stars, the Chaos Drives which could contain the Chaos Emeralds' mystical energies, the Artificial Chaos units, the Heal Unit, and the Bomb Unit. He was also behind the creation of incredible creatures such as the Biolizard and Shadow the Hedgehog (the latter of which used alien DNA), both of whom are powerful, nearly unstoppable and capable of harnessing the power of the Chaos Emeralds. Additionally, he was a skilled archaeologist as demonstrated in his research of the Gizoid and the Fourth Great Civilization where he uncovered many of their secrets from ancient stone tablets and papers.


Maria Robotnik

A photo of Gerald and his granddaughter, Maria.

Maria Robotnik was Gerald's granddaughter and undoubtedly the most important person in his life. Gerald was extremely fond of Maria and loved her dearly. Overall, she meant everything to him and was the jewel of his eye.[1][9] In addition, Gerald also made Maria's first name the password for many of his secret files and devices, indicating that she was very prominent to Gerald.

After Maria was diagnosed with Neuro-Immune Deficiency Syndrome, Gerald's main priority was her well-being, and nearly all his late research was dedicated to saving her life. Because of Maria, Gerald would break his own ethical standards and take enormous risks to find her a cure, such as leading Project Shadow to develop a cure despite finding the research unethical,[10] handing over Emerl to the government to get more time to find a cure for her despite Emerl posing an imminent danger,[23] and contacting Black Doom for help. He also held great trust in her, as he entrusted Shadow to her when the military attacked.[10]

When the ARK was shut down, Gerald's only concerns was Maria's safety. When he later learned that Maria had been killed, Gerald lost all reason to live and felt responsible for her demise since his research led to the terrible accident that killed her.[1] Eventually, he went mad with grief.[9] Gerald would then devote the remainder of his life to avenge Maria by wiping out humanity, whom he blamed for his loss.

Shadow the Hedgehog

Shadow the Hedgehog is Gerald's greatest achievement of his scientific career, an immortal and intelligent being. Gerald was the one who created Shadow, but while the government wanted to use Shadow to produce an "immortality formula," Gerald planned for him to provide a way to develop a cure for the fatal sickness afflicting his granddaughter, Maria. However, Gerald wished not for Shadow to become the government's weapon and gave him a "soul" similar to Maria's so he could choose not to fight and even help cease conflict.[6][29]

While Shadow was created to help him save Maria, Gerald cared a great deal about Shadow as an individual and considered him his own son. Gerald also held great faith in him as he entrusted him to correct his past mistakes by defeating the Black Arms and wholeheartedly hoped he could help mankind. When Gerald later went mad with grief over losing Maria, however, Gerald used Shadow as his tool to get revenge at humanity, going as far as to alter his memories to ensure he would carry out his plans.



In other media

Archie Comics

Gerald Robotnik in the Archie Comics.

In the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics, Gerald Robotnik was an Overlander, the maternal grandfather of Dr. Robotnik, and a member of the House of Ivo. Much like in the games, Gerald worked on Project: Shadow in hopes of finding a cure for the Neuro-Immuno Deficiency Syndrome afflicting his granddaughter, Maria Robotnik. Gerald created Shadow the Hedgehog but was captured by G.U.N. and forced to work for them. When Gerald learned that the military had killed Maria, he secretly made a program that would destroy Mobius as revenge before he was executed. A year after his awakening, Shadow encountered a digital version of Gerald who helped him uncover his purpose.

Following the events of Worlds Collide, Gerald became virtually indistinguishable from his game counterpart.

Sonic X

Gerald Robotnik in Sonic X.

In the anime series Sonic X and its comic series published by Archie Comics, Gerald Robotnik, much like in the games, was a human from earth and the grandfather of Maria Robotnik and Dr. Eggman.

Like in the games, Gerald was a scientific genius who worked on Project Shadow. Eventually, Gerald's research led to the creation of Shadow the Hedgehog who became close to Maria, but G.U.N. arrived sometime after to forcefully shut down the project when it was deemed too dangerous. Gerald himself was incarcerated on Prison Island where he learned that Maria had been killed by the military. Consumed by thoughts of revenge, Gerald created a program that would destroy the earth with the Space Colony ARK before he was executed.


"This is a death sentence for every human being on Earth. If my calculations are correct, the Space Colony ARK will impact the Earth in 27 minutes and 53 seconds. All of you will be destroyed, along with your beloved planet Earth. I plan to give you a taste of my revenge once all the seven Chaos Emeralds are collected. Once I initiated this program, it cannot be disabled. All of you ungrateful humans, who took everything away from me, will feel my loss and despair!"
—Gerald's last message before his execution, Sonic Adventure 2
"Shadow, my son. If you're listening to this, then the worst has happened. You need to know the truth. The government plans to shutdown this research facility. The government plans to cease all of my research and imprison all who know about you. I made a terrible mistake, Shadow. It's all my fault, making contact with that comet. Now, listen very carefully. In 50 years, the Black Comet will return. They plan to harness its powers to destroy this planet. The only way to stop them was to develop a way to use the very power they intended to use against them. Shadow, it's up to you, and only you can stop them! I developed the Eclipse Cannon. It's the only weapon that can destroy that Black Comet. Shadow, you are the only hope to save mankind as we know it. The future of this planet depends on... you."
—Gerald's message to Shadow in order to defeat the Black Arms, Shadow the Hedgehog


  • In the official game guide for Sonic the Hedgehog (2006), Sonic the Hedgehog: Official Game Guide, Gerald's name was mistakenly written as "Gerard." It should be noted that Japanese people pronounce the "r" and "l" sounds the same way.
  • When closely examining Gerald's picture in Shadow the Hedgehog, his eyewear has swirls, which is a typical Japanese trope to indicate one's glasses were thick.
  • After Gerald's rant, he was asked if he had any further words, to which he replies "no" before a squad is signaled. This is meant to imply that Gerald was sentenced to death by firing squad.
  • According to Sonic Chronicles: The Dark Brotherhood, Gerald had written a book on the Fourth Great Civilization called "Fourth Great Civilization.[8]


Concept artwork






See also


  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 Prima Development (20 June 2001). "The Beginning". Sonic Adventure 2: Prima's Official Strategy Guide. Prima Games. pp. 2–3. ISBN 978-0761536147.
  2. 2.0 2.1 2.2 2.3 Sonic Adventure 2 (Dreamcast) United States instruction booklet, p. 12.
  3. Sonic Adventure 2 (Dreamcast) Japanese instruction booklet, pg. 27.
  4. Backbone Entertainment, Sega Studio USA (24 November 2006). Sonic Rivals. Sega. Area/Level: Meteor Base Zone (Shadow's version). "Eggman Nega: Heh heh heh... I'm here to change my destiny! I come from a long line of brilliant scientists, but that lineage was disrupted with Dr. Eggman's failures!"
  5. 5.0 5.1 Sonic Team (3 May 2002). Sonic Adventure 2. GameCube. Sega. Area: Before Route 280. "Shadow the Hedgehog: The professor said his life's work was dedicated to all of those who live down there. He once told that the reason for his existence was, making people happy through the power of science."
  6. 6.0 6.1 6.2 6.3 6.4 6.5 Sonic Team (27 February 2004). Sonic Battle. Game Boy Advance. Sega. Area: Gimme Shelter. "Rouge the Bat: He was not interested in researching weapons. He was researching a way to bring happiness and hope to all people. But, he was forced by the government and by the military to use his research for war. That's why he gave you and Gizoid a "soul." A soul identical to his beloved granddaughter, Maria."
  7. Backbone Entertainment, Sega Studio USA (7 December 2007). Sonic Rivals 2. PlayStation Portable. Sega. Area: Frontier Canyon Zone. "Doctor Eggman: He apparently got some old files from my late grandfather, Professor Gerald. Those writings tell of an interdimensional beast called the Ifrit, and Eggman Nega wants to release it!"
  8. 8.0 8.1 Prof. Gerald Robotnik, Codex, Sonic Chronicles: The Dark Brotherhood
  9. 9.0 9.1 9.2 9.3 9.4 9.5 Gerald Robotnik's diary in Sonic Adventure 2.
  10. 10.00 10.01 10.02 10.03 10.04 10.05 10.06 10.07 10.08 10.09 10.10 Enterbrain (10 October 2001 ). "50年前の真実". ソニックアドベンチャー2パーフェクトガイド (in Japanese). ISBN 978-4757706255. Retrieved February 5, 2007.
  11. Sonic Chronicles: The Dark Brotherhood official website. Characters: Shadow the Hedgehog. Sega. Archived from the original on 24 July 2008. Retrieved on 4 July 2016. "Shadow is an artificially-created life form designed by the renowned scientist, Professor Gerald Robotnik, at the height of his career. His trademark hover shoes propel him at extreme speeds that rival those of Sonic and he has the ability to distort time and space using "Chaos Control.""
  12. 12.0 12.1 12.2 12.3 12.4 Sonic Team (November 18, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: Final Haunt. "Gerald Robotnik: If you're listening to this then the worst has happened... you need to know the truth. The government plans to shut down this research facility. The government plans to cease all of our research... and imprison all who know about you. I made a terrible mistake, Shadow. It's all my fault... making contact with that comet."
  13. Sonic Team (November 18, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: Final Haunt. "Black Doom: The professor was in development of the ultimate life force but he needed my help. So we made a deal... I helped him and he promised to deliver me the SEVEN Chaos Emeralds."
  14. 14.0 14.1 14.2 Sonic Team (November 18, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: Final Haunt. "Gerald Robotnik: Shadow... it's up to YOU and only YOU can stop them! I developed the Eclipse Cannon... It's the only weapon that can destroy that Black Comet. Shadow, you are the only hope... to save mankind as we know it. The future of this planet depends on... YOU!"
  15. File:Biolizard file 2.png
  16. Sonic Team (December 15, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: The Last Way. "Gerald Robotnik: .奴らは50年後、間違いなく再びこの星を訪れる...この星を我が者とするために!奴らの脅威に抵抗するためには、奴らの力を利用するしかなかったのじゃ...シャドウ、お前の体には、唯一奴らに抵抗できる能力が宿っておる。奴らの彗星を砕くための光学兵器エクリプスキャノンも用意した...、お前はワシら人類にとっての希望の光として生まれたのじゃ。この星の未来を、頼む... (They will surely visit this planet 50 years later... To make it theirs! In order to oppose their threats, I had no choice but to put their power to use... Shadow, there's an ability dwelling in your body that is the only way to resist them. I have also prepared the optical weapon, Eclipse Cannon, for crushing their comet... You were born as the light of hope for us humans. )"
  17. Prima Development (20 June 2001). "Artificial Chaos Series". Sonic Adventure 2: Prima's Official Strategy Guide. Prima Games. p. 17. ISBN 978-0761536147.
  18. Sonic Team (November 18, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: Lost Impact. "Maria Robotnik: Please, Shadow, I need your help! My grandfather's experiments... something's gone horribly wrong."
  19. Sonic Team (November 18, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: Lost Impact. "Maria Robotnik: Those liquid creatures are the experiment by-products, based on a god of an ancient culture.."
  20. Prof. Gerald's Journal 1-2
  21. Prof. Gerald's Journal 3
  22. Sonic Team (December 15, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: The Last Way. "Gerald Robotnik: この研究所は政府の手によって封鎖されるであろう... 研究資料はもちろん、ワシや研究所の仲間達も、幽閉されてしまうやもしれん。ワシが犯してしまった過ちによって...、あの彗星と悪魔と、接触してしまったばっかりに... (This research establishment may have its funds frozen by the hands of the government... The research materials, as well as my colleagues in the research establishment, will most likely get incarcerated... Due to the mistake that I have committed... Just for contacting that comet and the devil...)"
  23. 23.0 23.1 Prof. Gerald's Journal 4-5
  24. Prof. Gerald's Journal 6
  25. Sonic Team (27 February 2004). Sonic Battle. Game Boy Advance. Sega. Area: Ending sequence (Emerl's Episode). "Shadow: This was Gerald's final program... Should a weapon go out of control, the weapon will terminate itself..."
  26. 26.0 26.1 Sonic Team (November 18, 2005). Shadow the Hedgehog. PlayStation 2. Sega. Area: Lost Impact (Expert Mode). "Gerald Robotnik: Shadow? It is I. I hear that my research experiments have escaped and running loose... The positive and negative electrode connectors must have been reversed! Guess I must be getting old..."
  27. Prof. Gerald's Journal 7
  28. Sonic Team (3 May 2002). Sonic Adventure 2: Battle. Nintendo GameCube. Sega. "Amy Rose: What's all that writing on the walls anyway? Did you write that?"
  29. 29.0 29.1 Prof. Gerald's Journal 8
  30. Shadow the Hedgehog (Nintendo GameCube) United States instruction manual, p. 9

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