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

Professor Gerald Robotnik (simply known as Gerald Robotnik) is the posthumous villain of the videogame Sonic Adventure 2 and the "Shadow Saga" of Sonic X.

He was a brilliant but tragic scientist who once used his great intellect for good, but then plotted to destroy humanity as revenge for the death of his granddaughter Maria. He is also the grandfather of Doctor Eggman, and the indirect cause of his turn to villainy.


50 years ago, Gerald Robotnik was a respected researcher, considered by many to be one of the greatest scientific minds in the world. At the personal request of the president, he was offered a position onboard the Space Colony ARK by the United Federation, who wished to create "The Ultimate Lifeform", a being that could live forever. The military hoped to use the discovery of an "immortality formula" for weapons research, but Gerald refused the offer, believing that they were crossing the moral boundaries of nature. However, upon discovering that his beloved granddaughter, Maria Robotnik, was terminally ill, he changed his mind and accepted the position, in the hopes that he could use the research to discover a cure for her disease. Many researchers did not believe the creation of the "Ultimate Lifeform" to be possible, and began to name to project 'Project Shadow' due to it's apparently unreachable goal, as well as the level of secrecy the project required. Gerald liked the name, and it stuck.

Professor Robotnik initially experimented on the Chaos Emeralds and researched the results of applying Chaos Energy to living beings. The experiments proved successful and resulted in the creation of the Chaos Drives, which were used by the military as a power source for their robots. He even learned about the history of the Knuckles Clan and the destructive water being Chaos. Fascinated by the legends, he created the Artificial Chaos series and a shrine similar to the one on Angel Island deep within the ARK.

Progressing on the next stage of Project Shadow, Gerald began experimenting on lizards, due to their ability to regenerate limbs; the result was the prototype Biolizard. Initially showing all desired traits as it matured, the prototype required a life support system fueled by Chaos Drives in order to survive, and it lacked to strength to even walk, despite the strength in its tail and neck. Possessing the mind of a primitive animal, the Biolizard became more unruly and difficult to control as it continued growing. With no choice, Gerald had to encapsulate the creature.

Sometime later, Professor Robotnik came in contact with the extraterrestrial Black Doom, and, using his DNA, created a much more advanced being; Shadow the Hedgehog, who became like a son to him and a good friend to his grandaughter. Upon learning that Black Doom and the Black Arms race wished to harvest the human race as food, Professor Robotnik secretly developed the Eclipse Cannon in order to destroy them the next time they visited Earth.

However, the government soon concluded that Gerald's experiments were too dangerous to humanity, and sent GUN to the ARK to neutralize them. Gerald managed to survive, but was immediately captured by the government and sent to Prison Island, where he was forced to continue his experiments. The government used him as a scapegoat, publicly declaring that the ARK had been shut down due to a devastating lab accident he had caused. GUN later managed to capture Shadow and sent him to Gerald, who discovered that Maria was among the casualties of the raid, and was stricken with grief over how his own research claimed the life his beloved granddaughter, despite the fact that it was meant to save her.

Losing his sanity as well as his will to live, he was driven insane and became obsessed with exacting revenge on humanity for betraying his family. He made plans to send the ARK colliding with the Earth and destroy the planet once the 7 Chaos Emeralds were collected, programming Shadow and the Biolizard to ensure his plan's success. Unfortunately for Professor Robotnik, the government feared that Gerald would soon retaliate and had him executed, but not before the mad scientist left one final recording of his execution, in which he explained his plans for revenge.

Sonic X

Prof. Gerald Robotnik also makes an appearance as the true antagonist in the Shadow Saga in the animated TV series Sonic X. His story is very similar towards the story in Sonic Adventure 2, but with some differences. Some differences include; being unclear if Gerald Robotnik came in contact with Black Doom to create Shadow the Hedgehog.


I don't quite know what happened or what went wrong. Was it a mistake to create the ultimate life form? I thought it would be something that could benefit mankind. But then the military soldiers landed on the colony that day. They were sent to destroy the research project I had been working on. My colleagues at the research facility, my granddaughter Maria. I hope you are all safe. The colony was completely shut down. Probably to keep it from falling into the wrong hands. The ARK was shut down under the premise that there had been an accident. I found Maria's name among those who died when the ARK was shut down. She meant everything to me and I couldn't bear the thought that she died because of my research. I lost everything. I had nothing else to live for. I went insane. All I could think about was to avenge her...Somehow, someway. I got scared as I no longer was able to control my thoughts. All I could think about was that I wanted it all to end. Based on my original projections, I was able to complete my project, Shadow. I designed it's mind to be perfect, pure. I will leave everything to him. If you wish, release and awaken it, to the world. If you wish to fill the world with destruction.
~ Professor Gerald's diary.
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!
~ Professor Gerald's last recorded message to the world before his execution.



  • In the photograph of him and Maria on Sonic Adventure 2, he was skinnier than his grandson. However, in the photograph of him and Maria on Shadow the Hedgehog, he is shown to be much bigger.
    • Also, his glasses on the photograph in Sonic Adventure 2 are smaller, but on Shadow the Hedgehog, they are bigger and take up nearly twice the space.
  • There seems to be a continuity error involving Gerald. G.U.N. raided the ARK to either kill or imprison everyone on board. They somehow captured Shadow on Earth, but on the day of the raid, Gerald is imprisoned and stripped of all use of money and technology. This makes it impossible for him to record his motives on his diary, reprogram the ARK to fall to Earth, reprogram Shadow's brain to think he has to destroy the world, or produce a 50-year-old video of his own execution.
    • It is most likely that during his stay on Prison Island, he was ordered to reprogram Shadow to be loyal to the government. But instead, he altered Shadow's memories to make him think that revenge was what Maria wanted, and secretly stored the revenge program on his person, which he uploaded onto the ARK once he returned to it 50 years later.


            Sonic the Hedgehog logo Villains

Eggman Empire
Dr. Eggman | Orbot | Cubot | Metal Sonic | Mecha Sonic | Silver Sonic | Mecha Knuckles | Badniks | Tails Doll | E-100 Alpha | E-101 Beta | EggRobo | Eggman Enterprises | MeteorTech | SCR-HD | Master Core: ABIS | Time Eater | Jackal Squad | Infinite | Replicas

Team Dark
Shadow the Hedgehog | Rouge the Bat | E-123 Omega

Team Hooligan
Fang the Sniper | Bark the Polarbear | Bean the Dynamite

Babylon Rogues
Jet the Hawk | Wave the Swallow | Storm the Albatross

Eggman Nega's Forces
'''Eggman Nega''' | Metal Sonic 3.0

Deadly Six
Zavok | Zazz | Zeena | Master Zik | Zomom | Zor

Black Arms
Black Doom | Devil Doom | Eclipse the Darkling

Nocturnus Clan
Imperator Ix

Dr. Eggman | Hard-Boiled Heavies (Heavy King) | Metal Sonic

Sonic Boom
Charlie | D-Fekt | Dave the Intern | Dr. Eggman | Hypnobot | Lyric the Last Ancient | Metal Sonic | Morpho | Shadow the Hedgehog | Swifty the Shrew

Babylon Guardian | Bearenger the Bear | Biolizard | Black Knight | Captain Whisker | Carrotia the Rabbit | Chaos | Dark Gaia | Dark Gaia's Minions | Dr. Fukurokov | Erazor Djinn | Fockewulf the Wolf | King Boom Boo | Iblis | Ifrit | Super Sonic | Mephiles the Dark | Merlina | Scorpius | Solaris | Wendy Witchcart

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