Quotation1 All of you ungrateful humans, who took everything away from me, will feel my loss and despair! Quotation2
— Gerald Robotnik, Sonic Adventure 2

Professor Gerald Robotnik (プロフェッサー・ジェラルド・ロボトニック Purofessā Jerarudo Robotonikku?) is a fictional character from the Sonic the Hedgehog series. He was a human scientist and the grandfather of Maria Robotnik and Dr. Eggman. 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 to lead Project Shadow, a medical program for researching immortality, which he accepted in hopes of finding a cure for a fatal illness afflicting Maria. 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 was 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 brown 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 remake, 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.


Early life

Not much is revealed about Gerald's past, although it is hinted that he comes from a long line of brilliant scientists.[2] The greatest mind of his time, Gerald set out to help the world by dedicating his life's work to the people of earth and bring them happiness and hope through science.[3][4][5] During his carrier, Gerald accomplished many great things, his most remarkable creation being the Space Colony ARK, the world's first space colony which he designed.[3][6] Other accomplishments included discovering and researching an interdimensional beast called the Ifrit,[7] and being the first to propose the existence of the Fourth Great Civilization which he wrote a book about called The Fourth Great Civilization.[3]

Eventually, Gerald had a granddaughter named Maria Robotnik, who he became extremely fond of.[8] 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][3][9]

Project Shadow

Over fifty years prior to Shadow the Hedgehog, Gerald, at the height of his career, got a letter from the by then-President of the United Federation who requested his help with a medical project named "Project Shadow" which was meant to research immortality and create an "immortality formula."[3][9][10] Initially, Gerald stubbornly refused this request, believing they were crossing the limits of man and that this research could be used for war. 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.[9]

In the first stages of Project Shadow, Gerald researched the Chaos Emeralds, resulting in the creation of the Chaos Drives, during tests to apply chaos energy to living beings. When those test proved successful, Gerald and his colleagues moved onto creating an immortal creature dubbed the "ultimate life form".[9] During this development, Gerald needed help for his research. He thus contacted Black Doom, the alien leader of the Black Arms from the Black Comet, and they made a deal: Gerald would have his creation deliver the seven Chaos Emeralds to Black Doom in fifty years and Black Doom would help Gerald with his work, even providing his blood as DNA for the project.[11] However, Gerald discovered Black Doom's plans to use the Chaos Emeralds to enslave the human race. Realizing his mistake, Gerald secretly plotted against Black Doom by developing the Eclipse Cannon to destroy the Black Comet and the Black Arms upon their return.

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.[9] In addition to an 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.[12] Despite these results, Gerald moved on with the project. Using the DNA of Black Doom,[3] Gerald created a new version of the Biolizard, but with another physique,[9] dubbed "Shadow the Hedgehog." Unwilling to make Shadow a weapon though, Gerald gave him a heart and soul similar to Maria's so he would not breed conflict.[5] 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.[13]

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.[14][15][16]

The Gizoid

During Project Shadow,[3] 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. Theorizing the Gizoid's full potential should it be fully restored, Gerald realized he had uncovered a horrible weapon.[17]

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.[18]

Government and Shadow

When Shadow neared his completion, Gerald learned the government had become uneasy about Project Shadow following his contact with the Black Arms and they considered cutting funding.[3][19] Unwilling to let Maria die, Gerald made a big risk and offered the Gizoid as a bribe to the government to keep Project Shadow going.[3][20] 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 reprogrammed the Gizoid with free-will and emotions, giving it a heart and soul similar to Maria's so that it could not become a weapon, like Shadow.[5][21]

His Creation

Gerald and Black Doom overseeing Shadow's awakening.

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. Learning however that the government planned to cease his research after deeming Shadow a threat to mankind, Gerald prepared a contingency video for Shadow to explain his intention for him to stop the Black Comet in fifty years.

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.[22] Fortunately, Shadow 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.[3] 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][9]

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][6] Meanwhile, when it was released to the public that the ARK was shut down due to an accident, Gerald was blamed for causing it.[9] When the military later found Shadow 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 his loss, Gerald began to lose control of his thoughts as he could only think of avenging Maria and ending everything, something which terrified him.[8] During this period, while 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.[23]


Gerald in his last moments.

In the end, Gerald lost his grip on reality and went insane, devoting himself to avenging Maria by destroying humanity.[8] 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,[3] and set as well the Biolizard up to ensure this. Gerald then brainwashed Shadow,[1][3] altering his memories so that he would carry out his plan. 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.[24]

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 research surrounding Shadow, the Eclipse Cannon, Emerl and the Ifrit 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.

Gerald's plan to destroy Earth was set into motion when Eggman awoke Shadow. Like Gerald had intended, Shadow set out to destroy the world to avenge Maria, unaware that he was carrying out Gerald's will. Once the Space Colony ARK was set on a collision course with earth, Gerald's last video recording was played around the world. Gerald's doomsday plan was averted however by Sonic the Hedgehog and, ironically, Shadow, who managed to recover his true memories of Maria. During the Black Arms invasion of earth, Gerald's contingency video to Shadow was played worldwide as well, where he explained his plans for Shadow to save mankind from the Black Arms, which gave Shadow the resolve needed to defeat Black Doom. Realizing they had been wrong about Gerald all along, the President and the Commander decided to pay homage to him by working towards a brighter future.


Before his descent, 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.[4][5] 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.[22]

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.[5][9] 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 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.[25]

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. 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,[6][26] only matched by his grandson Eggman.[3]

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 as the ultimate weapon known as the Eclipse Cannon, the Chaos Drives which could contain the Chaos Emeralds' mystical energies, and the Artificial Chaos units. He was also behind the creation of incredible creatures such as the Biolizard and Shadow the Hedgehog (the latter of which used alien DNA). 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.


Maria Robotnik

Gerald and Maria Photo Shadow the Hedgehog

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][8] 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,[9] handing over Emerl to the government to get more time to find a cure for her despite Emerl posing an imminent danger,[20] and contacting Black Doom for help. He also held great trust in her, as he entrusted Shadow to her when the military attacked.[9]

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.[8] 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.[5][25]

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 brainwash him to ensure he would carry out his plans.[3]


Space Colony ARK

Main article: Space Colony ARK
Ark by RobbieGlazer

The Space Colony ARK.

The former home of Gerald, Maria, the would-be commander of G.U.N., and various researchers and soldiers, the ARK was a gigantic space colony where great research was performed. The entire place also worked as a life support system for Maria. While Gerald focused on making inventions for the good of mankind, little-known devices of mass destruction were being made (the Ultimate Lifeform and the Eclipse Cannon), mostly under the influence of the military and preparations against Black Doom. Others who lived aboard the ARK included Shadow (who protected the ARK from danger), the Biolizard and Emerl. When Shadow was deemed a threat to humanity, the ARK was shut down with several casualties. The ARK was later rediscovered by Dr. Eggman, who used it as a temporary base.

Eclipse Cannon

Main article: Eclipse Cannon

The Eclipse Cannon is an extremely powerful weapon that is located inside the "nose" of the Space Colony ARK. It is powered by Chaos Emeralds and can destroy planets or even pierce stars with all seven. Gerald built it to destroy the Black Arms when they would return to Earth after fifty years, but after he went insane, he reprogrammed it to send the ARK flying into the Earth the next time it was activated with all seven Emeralds. Eventually, it was used for its original purpose.

Artificial Chaos

Main article: Artificial Chaos

Artificial Chaos are Gerald's first noteworthy creations. They resemble Chaos from Sonic Adventure and are most likely modeled after him as Maria states that Gerald created them based on "a god of an ancient culture". The Artificial Chaos are made up of a core (the head, shaped like that of Chaos 0) and trillions of nanobots that both protect the core and provide the body for it. While the Artificial Chaos seen in Shadow the Hedgehog had red, half-closed eyes and red marking on their heads, the ones in Sonic Adventure 2 have larger green eyes and an emblem on their foreheads.


Main article: Biolizard

Biolizard was the Prototype of the Ultimate Life. It was a giant lizard hooked up to a life support system. The Biolizard was deemed a failure as it went out of control and had to be sealed up. After Gerald went insane, he programmed the Biolizard to stop anyone from hindering the ARK crashing into the Earth, but it was stopped.

Shadow the Hedgehog

Main article: Shadow the Hedgehog

Perhaps Gerald's most brilliant achievement, this was the finished result of Project Shadow, the immortal Ultimate Lifeform who would never age. Shadow was created after Gerald had gone into a pact with the alien leader Black Doom, using his alien blood to create Shadow with a promise that Shadow would help Black Doom retrieve the Chaos Emeralds fifty years later. However, Project Shadow was canceled a week after Shadow was created, and Shadow was eventually captured and hidden away by G.U.N.

Heal Units

Main article: Heal Unit

Portable box-like devices that send out energy that replenishes health and is still used to this day by G.U.N. The Heal Unit may have inspired the creation of the Heal Cannon, a Bazooka-like weapon that fires shots with the same healing capabilities. Maria Robotnik feels it is Gerald's greatest creation.

Bomb Units

Main article: Bomb Unit

The Bomb Units are portable and highly explosive box-like bombs. These are used in Shadow the Hedgehog to break walls and find secret passageways. Their design is very similar to the Heal Units' design.

In other media

Archie Comics

Gerald Robotnik Archie v2

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 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.


  • In the official game guide for Sonic the Hedgehog (2006), Sonic the Hedgehog: Official Game Guide, Gerald's name was mistakenly written as "Gerard."
  • 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.



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. Backbone Entertainment, Sega Studio USA (December 7, 2007). Sonic Rivals. PlayStation Portable. Sega. Area: Meteor Base Zone. "Doctor 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!"
  3. 3.00 3.01 3.02 3.03 3.04 3.05 3.06 3.07 3.08 3.09 3.10 3.11 3.12 3.13 Prof. Gerald Robotnik, Codex, Sonic Chronicles: The Dark Brotherhood
  4. 4.0 4.1 Sonic Team (May 3, 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."
  5. 5.0 5.1 5.2 5.3 5.4 5.5 Sonic Team (February 27, 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."
  6. 6.0 6.1 6.2 Sonic Adventure 2 (Dreamcast) North American manual, p. 12
  7. Backbone Entertainment, Sega Studio USA (December 7, 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 8.2 8.3 8.4 Gerald Robotnik's diary in Sonic Adventure 2.
  9. 9.00 9.01 9.02 9.03 9.04 9.05 9.06 9.07 9.08 9.09 9.10 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.
  10. 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."”
  11. 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."
  12. File:Biolizard file 2.png
  13. 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. )"
  14. Prima Development (20 June 2001). "Artificial Chaos Series". Sonic Adventure 2: Prima's Official Strategy Guide. Prima Games. p. 17. ISBN 978-0761536147.
  15. 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."
  16. 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.."
  17. Prof. Gerald's Journal 1-2
  18. Prof. Gerald's Journal 3
  19. 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...)"
  20. 20.0 20.1 Prof. Gerald's Journal 4-5
  21. Prof. Gerald's Journal 6
  22. 22.0 22.1 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..."
  23. Prof. Gerald's Journal 7
  24. Sonic Team (May 3, 2002). Sonic Adventure 2. GameCube. Sega. "Amy Rose: What's all that writing on the walls anyway? Did you write that?"
  25. 25.0 25.1 Prof. Gerald's Journal 8
  26. Shadow the Hedgehog (PlayStation 2) instruction manual, p. 7

Main article | Gallery | Beta elements | Staff | Glitches | Re-releases (Battle | 2012)

Main article | Gallery | Library Sequences | Staff | Glitches