Dr. Ivo "Eggman" Robotnik/Synopsis

The story of the power-hungry, egg-shaped mad scientist Dr. Eggman, the main antagonist of the Sonic the Hedgehog franchise as well as Sonic's archenemy.

Early Games
Originally known exclusively as Dr. Ivo Robotnik in the localizations outside of Japan, Dr. Eggman did not have much of a story going for him. In the first game, he was trying to conquer South Island and create his own mechanical paradise known as Eggmanland and was eventually foiled by Sonic the Hedgehog.

In the second game of the main Genesis series, Sonic's friend Miles "Tails" Prowler joins the blue hedgehog to stop Robotnik, who has conquered West Island. Sonic eventually defeats Doctor Robotnik in a skirmish on the doctor's space station, the Death Egg. In GameGear version of Sonic the Hedgehog 2, the good doctor takes Tails for ransom, asking for 6 Chaos Emeralds in return.

In Sonic CD, Doctor Eggman arrives in a world with seven gems that can control time. Planning ahead, he created a robotic version of Sonic, dubbed Metal Sonic to keep him busy.

In the third game of the main series, after being damaged by Sonic, Eggman's space station, the Death Egg, started falling out of orbit. It lands on a floating island known as Angel Island. Here he meets Knuckles the Echidna, the last member of his tribe, who was responsible for guarding the Master Emerald, which kept the island levitating. Eggman tricks Knuckles into believing that Sonic would come to steal his emerald, and so makes him Sonic's enemy.

In Sonic and Knuckles expansion, after once again being damaged, the Death Egg falls onto Angel Island once again, and lands in a crater. As Doctor Robotnik prepares his Death Egg for a new launch, he drops a bomb on Knuckles, which infuriates him and sends on a search for Sonic.

The complete Sonic 3 & Knuckles ends with the heroes destroying Eggman's robotic creations on the Death Egg and taking the Master Emerald back from Robotnik during the Doomsday event.

Eggman has appeared as the main villain of nearly every other earlier Sonic title, such as SegaSonic the Hedgehog, Knuckles' Chaotix, Sonic Chaos, Sonic Triple Trouble, Sonic Labyrinth, Sonic the Fighters, Sonic 3D Blast, and Sonic R, with Sonic defeating Eggman at the end of each except SegaSonic the Hedgehog (in which there is no boss battle), Knuckles' Chaotix (in which Knuckles and his team fights him), and Sonic Labyrinth (in which one of Robotnik's creations is the final boss).

In Sonic Labyrinth, Eggman manages to sneak up to Sonic while he was sleeping and replaces his shoes with Slowdown shoes, ignoring the fact that he could have just destroyed Sonic right there.

Later Games
Sonic Adventure games reveal some parts of Robotnik's backstory and unite the use of his alias "Eggman" (in English versions of Sonic Adventure) and his surname "Robotnik" (Sonic Adventure 2 features first official appearance of the name "Robotnik" in Japanese versions). Sonic Adventure 2 reveals that Eggman's cousin Maria and grandfather Professor Gerald Robotnik (who was Ivo's hero and idol) were killed by the government's agents. That act was shocking for Ivo Robotnik, turning him into the terrorist, trying to destroy the government and create his own ideal Eggman Empire (and, in later games, the industrial Eggmanland).

Sonic Heroes
Metal Sonic, now known as Neo Metal Sonic, rebels against Dr. Eggman and locks him on his own flagship. In the meantime, Metal Sonic impersonates the doctor, fighting the heroes and gathering data to upgrade his own battle capabilities. The real Doctor Eggman with his voice secretly high-pitched as a cover, coordinates Team Chaotix and waits for the detectives to free him and later unites all of the teams to fight Neo Metal Sonic, also reminding them about the power of Chaos Emeralds. After Neo Metal Sonic was defeated and reverted back to his original form, Eggman attempts to sneak away from paying Vector, only to spotted by him, forcing him to run away from the now angry Team Chaotix.

Shadow the Hedgehog
Eggman is the secondary antagonist and the Eggman Empire is one of the factions which Shadow the Hedgehog can ally himself with. Dr. Robotnik can either give missions to the hedgehog or fight him as a boss. Robotnik's forces take part in defending the planet from Black Doom's alien army and the doctor himself ends cheering on the protagonist in the canonical "Last Story" ending. During the final boss (if the player continues fighting for 8–10 minutes), Eggman reveals to everyone, including Shadow, that the Shadow they've been working with since Sonic Heroes is indeed the real and original Shadow. After Black Doom is defeated, Eggman tries to go take the Chaos Emeralds, only to be chased by Knuckles.

Sonic Riders
Eggman is the main antagonist and searches for the treasure in Babylon Garden, getting the Babylon Rogues to win the Chaos Emeralds for him, however, is disappointed at the treasure being a carpet (unaware that it was a magic carpet). In Sonic Riders: Zero Gravity, he attempts to use MeteorTech robots and Arks of the Cosmos to take over the world, but they turn on him, and are destroyed by Sonic. In Sonic Free Riders, he disguises himself as "King Doc" (also called himself "King Doc of Toreggmania) and hosts a Grand Prix, having reprogrammed Metal Sonic to race for him and collect data from Sonic, Amy, Shadow, and Jet's teams, however, Metal Sonic betrays him yet again and collects the data for himself, but loses the last race to Sonic.

Sonic Rush
Eggman teams up with, seemingly, his "counterpart" from the Sol Dimension, Dr. Eggman Nega, to create an Eggmanland beyond all dimensions by abusing the Chaos Emeralds and Sol Emeralds, however, they are defeated by Sonic and Blaze. In Sonic Rush Adventure, they team up again, this time in the Sol Dimension, creating Captain Whisker to find the Jeweled Scepter for them so they can use it to awaken the Power of Stars. After Whisker is destroyed, they steal it themselves, but are defeated by Sonic and Blaze. Nega tries to use "Planet-Buster Laser" to undo the creation, but is interrupted by Marine the Racoon and ends up destroying their robotic Egg Wizard. Eggman survives and returns to the Chaos dimension.

Sonic Rivals
Eggman is imprisoned in a card by Dr. Eggman Nega, who is revealed to be Ivo Robotnik's descendant from 200 years in the future, who hates the good doctor for disrupting their line of brilliant scientists with his failures and wants him removed from the timeline. However, Eggman is released by Shadow and Silver and helps them get to Nega's base. In Sonic Rivals 2, he reprograms Metal Sonic as a mindless servant and has him team up with Shadow to stop Eggman Nega from releasing the Ifrit and destroying the world.

Sonic Unleashed
Eggman is once again the main antagonist. He awakens Dark Gaia in an attempt to take over the world and defeat Sonic. After he is defeated by Sonic and puts Dark Gaia back together, he is knocked into the distance by Dark Gaia, who will not take orders from him. He survives, however, and is last seen chasing his robot assistant Orbot into the distance for calling him a loser. The most pathetic loser in all the world, whose past efforts were utterly wasted.

Sonic Colors
Dr. Eggman is again the main antagonist and has opened an intergalactic amusement park pretending to have redeemed himself, however, he was really harvesting thousands of aliens called Wisps for use in the creation of a mind-control device which he planned on using to take control over the entire universe. When it fails, Eggman (in anger) finally snaps and decides to focus completely on killing Sonic, and attacks him with the Egg Nega Wisp (also known as Nega Wisp Armor). After his defeat, he is left in the middle of space with his robot assistants Orbot and Cubot to move his Eggmobile. This appearance has marked the first time in a 3D Sonic game to feature Eggman as the final boss.

Sonic the Hedgehog 4
In Episode I, which chronologically takes place after Sonic the Hedgehog 3 & Knuckles, Doctor Robotnik starts a new scheme and improves on some of his earlier creations to stand a better chance against Sonic. However, this does not slow the hedgehog down and he eventually defeats Eggman during a showdown aboard the E.G.G. Station. In Episode II, it shows that the good doctor is not finished yet and begins construction of his Death Egg Mark II around Little Planet. Sonic and his pal Tails chase Eggman across various locations before making their way onto the Death Egg Mark II itself. Although Robotnik had Metal Sonic by his side, he was ultimately defeated again by the heroes at the heart of the Death Egg.

Sonic Generations
In a surprise reverse twist from past 3D games, Classic and Modern Dr. "Eggman" Robotnik are not only the main antagonists, but the final bosses of Sonic Generations. Eggman finds a monstrous, supernatural entity, that he converts into a cybernetic organism, called the Time Eater, which he uses in an attempt to alter time and erase his previous defeats. He kidnaps and teams up with his past self from Sonic the Hedgehog 2, however, both Eggmans are defeated, destroying the Time Eater in the process, resulting in them being trapped in limbo, unable to escape. During this they realize they will never beat Sonic, and plan to get a teaching degree if they ever get out.

Sonic Lost World
Eggman somehow escapes limbo (and obviously does not take up a teaching degree) and tries to harness the power of the Deadly Six to take over the world, using a magic conch to torture them into submission, but they rebel against him, since Sonic took Eggman's conch and kicked it into the distance, forcing him and Sonic to work together to defeat them. After the Deadly Six are defeated, Eggman (who had faked his death during his alliance with Sonic to power a machine) turns on Sonic revealing he had been using him to defeat (and possibly kill) the Deadly Six, effectively becoming the true main antagonist. He is defeated by Sonic shortly after, and falls off the Lost Hex, seemingly to his death (though neither Sonic or Tails care, but this may be because they knew where he would land). It is revealed in the end that he survived by falling into soft dirt, but lost half his mustache due to a rabbit mistaking it for a carrot stalk while he was unconscious.

Sonic Forces
After somehow obtaining a mysterious and powerful gemstone know as the Phantom Ruby, Dr. Eggman began plans to make his biggest bid for world domination yet. Fueled by his hatred for Sonic the Hedgehog, Eggman incorporated the Phantom Ruby’s power into a disgraced squad leader and eventually converted him into his latest weapon; the enigmatic Infinite.

When his preparations were complete, Eggman commenced a worldwide assault and was soon confronted by Sonic and Tails. The doctor summons Infinite and duplicates of Sonic’s rivals to battle the blue hedgehog and seemingly succeed in destroying him. With Sonic finally gone, Eggman continued his invasion for six months with great success. Actually conquering 99% percent of the world with the remaining 1% still resisting his forces. While Eggman gave his enemies three more days to prepare for a final confrontation, The Resistance fought to weaken the Phantom Ruby's power, which was presumably being energized by the rebuilt Death Egg orbiting around the planet.

The Resistance eventually achieved in destroying the Death Egg with the help of Sonic the Hedgehog (who was revealed to be alive and well), a version of Sonic from an alternate dimension, and a remarkable new recruit usually referred to as the “Rookie”. Unfortunately, a backup generator hidden under Metropolis apparently managed to give the Phantom Ruby enough power for Eggman to have Infinite conjured up a sun and throw it at his enemies. Not only destroying the Resistance but also all other opposition on the planet’s surface. However, the Rookie used a Phantom Ruby Prototype he/she found to make the sun disappear, saving their allies and making Eggman retreat to his base.

As the heroes tackled the dangers of his base, Eggman played his trump card by installing the Phantom Ruby into a Death Egg Robot which empowers (or drains) the ruby so much that it overclocks, making the robot even more powerful than Infinite. Despite all its power however, the robot (and presumably the Phantom Ruby) was destroyed by the teamwork of both Sonic counterparts and the Rookie, thus foiling Eggman’s plans and releasing his gripping hold on the world.

Unlike in other 3D games, Eggman is not seen again following the destruction of his Death Egg Robot, so it is possible that he was destroyed along with it. However, since he has survived or escaped the destruction of previous mechs in earlier games, there is possibility he survived.