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Dr. Robotnik... Enemy. Master registration... Deleted. E-Series... Friends. Must save...

— E-102 Gamma, Sonic Adventure

E-102 (E-102 Ī Ichi-Zero-Ni?), codenamed γ or Gamma (ガンマ Ganma?),[3][4] is a character that appears in the Sonic the Hedgehog series. He was a high-tech marksman assault machine[5][2] and the second model in the E-100 Series of robots, created by Dr. Eggman[1][4] during the Chaos incident to aid in the destruction of Station Square.[6] Unlike the other models, however, Gamma's programming featured a critical flaw, which, unknown to Eggman, gave Gamma free will.[7] As a result, after joining the Egg Carrier's elite crew and noticing the doctor's cruelty, Gamma went rogue and abandoned his creator. He then assumed his own mission to "free" his robot brethren from his creator, and succeeded, though at the cost of his own life.

Concept and creation[]


Various concepts alongside E-102 Gamma's final design.

As designer of Sonic Adventure, Takashi Iizuka thought of including one of Dr. Robotnik's Badniks as a playable character. Wanting some kind of satisfying gameplay that was impossible to feature with Sonic, he decided to have shooting as Gamma's playstyle.[8]



E-102 Gamma, from Sonic Art Assets DVD.

E-102 Gamma was a humanoid robot colored in mainly red and white. He possessed no neck, his head and torso coming together in an almost ellipsoid shape. His torso was red with a wide and white vertical stripe down the middle and possessed a head light with a hexagonal gray frame on the right side. He also had gray mufflers surrounding the pelvis area and had the number "102" painted in white on the right of his large vertical stripe and the left side of his rear. His head meanwhile was small and platform-like with a yellow shade and green cylindrical eyes. He also had a hexagon-shaped disk hovering behind his neck, and a laser targeting scope on the right side of his head.

Gamma's shoulders were black vertical cylinders. Attached to each of them were Gamma's arms, which were long and designed with two joints; his left arm held Gamma's black-gray blaster while his right arm had a tri-digited hand with two points of articulation on each digit. Also, Gamma's right upper arm was red with yellow-orange cuffs, while the parts between his upper arms and forearms were gray. Gamma also possessed two long and inverted legs with five points of articulation and large, black feet with two sharp toes and roller wheels on the heels. The upper sections of his legs in particular were red while the rest of them were gray, except from his calves, which were thick and red with gray and yellow-orange cuffs.


Sonic Adventure[]

Sonic Adventure Gamma and Robotnik

Gamma with Dr. Robotnik upon his activation, from Sonic Adventure.

In Sonic Adventure, E-102 Gamma was created by Dr. Robotnik as the second unit in the E-100 Series to aid the doctor in his agenda to destroy Station Square and build Robotnikland on its ruins.[6] After his activation in the Final Egg, Gamma was ordered by his creator to pass a shooting range in the base to test his efficiency. Following this task, the doctor, wanting a good crew for his Egg Carrier, made E-102 fight his older "brother", E-101 Beta. After defeating Beta in combat, his first task on board involved capturing a frog that had absorbed Chaos' tail and held a Chaos Emerald that the scientist desired. The mission also served as a contest against his other "brothers", Delta, Epsilon, and Zeta.

To complete his task, Gamma went to Emerald Coast from Station Square to find the frog, who was Big the Cat's best friend, Froggy. After locating Froggy and snatching him out of Big's hands, Gamma went back to the Egg Carrier, where he reunited with the other robots, who claimed to have the right frog. When Dr. Robotnik came in, he was disappointed to see that his robots had failed at their mission but was delighted when he saw Gamma with Froggy. After that, the doctor disposed of the other E-100 Series robots to remodel them in front of Gamma; this event would be recorded in Gamma's memory. Following this, Robotnik made Gamma go to the prison cell of the Egg Carrier and get Birdie, a bird that was accompanied by Amy Rose. However, the robot accidentally entered another room where he stared at Beta being gruesomely remodeled by a machine, another event that would be saved in his memory. Though disturbed by this sight, he quickly disregarded this and returned to his mission. After finding Amy, E-102 strictly demanded her to give him Birdie, which she refused to do. After Gamma insisted, Amy proceeded by questioning him, and from this Gamma experienced illogicality in his programming due to a conflict of interests. He then asked her why she would risk her life to save something that was useless to her; Amy simply replied that he did not need to obey Robotnik. After this, Birdie flew up to Gamma knowing that his pink relative was inside. After a long stare into Birdie's eyes, perhaps triggering memories from his organic battery, Gamma realized that he needed to release them; he then proceeded to do this. Surprised and touched by this, Amy exclaimed that Gamma had to be different from the other robots and told him she would be his friend.

Shortly after, Gamma was called by Robotnik to kill Sonic and Tails at the deck of the Egg Carrier. A grueling battle ensued between Sonic and Gamma which ended when Amy intervened, begging them to stop and explaining to Sonic and Tails that Gamma was a friend. The two reluctantly submitted to Amy's pleads as Gamma backed down. As the Egg Carrier began to lose altitude and slowly fall to the earth below, Amy encouraged Gamma to free himself, explaining the virtues of friendship before they evacuated. While hovering to the Mystic Ruins, Gamma's life flashed before his eyes with pictures of Robotnik, the other E-Series robots, Amy and the Egg Carrier, flashing faster and faster until he saw Amy one last time and realized his purpose. Gamma determined that Dr. Robotnik was the enemy and deleted his master registration program. He then decided to begin a "rescue" mission, locating the rest of the E-100 Series robots and freeing the Animals trapped inside them.

Gamma first found and destroyed Delta in Windy Valley, then he located Epsilon in Red Mountain on Angel Island, and eradicated him as well, freeing the Animals. Afterward, he ran a scan to locate Zeta; his results showed that Zeta was not in any range of the Mystic Ruins or Station Square. Gamma realized that he had to be aboard the Egg Carrier, so he returned to the ship to find him. After destroying the upgraded and much more heavily fortified version of Zeta, he overlooked his progress, trying to locate the final E-Series model, E-101 Beta, knowing that he had to be on or around the Egg Carrier. He overlooked himself as the other E-Series robot that had also be "saved". On the deck of the Egg Carrier, while thinking, Beta flew by the east side of the Egg Carrier as the newly rebuilt E-101 Mark II. Gamma quickly moved to the center of the ship where Beta was waiting for him for the final confrontation. Despite Beta's numerous enhancements, Gamma eventually succeeded in destroying Beta.

Sonic Adventure Gamma exploding

Gamma self-destroying, later releasing the bird inside of him, from Sonic Adventure.

Before exploding, however, Beta gathered up one last ounce of strength and suddenly blasted Gamma at point-blank range, severely damaging him. As Gamma limped away from the battlefield, the bird that was inside Beta flew up close and stirred one final memory in Gamma, of a family of birds together. Gamma, realizing he needed to free his bird, did not activate his auto repair system. He then collapsed and self-destructed, freeing the pink bird inside, who united with the other bird, a family member whom it had been separated from.


Sonic Adventure[]

E-102 SA Fin

The pink bird inside Gamma flying away with its sibling, from Sonic Adventure.

In the immediate aftermath of his destruction, Gamma lost all of his memory.[9] After that, the pink bird inside of him and his brother reunited with their other brother, Birdie. The pink bird later followed Amy to Station Square after it was near devastated by Perfect Chaos.

Despite the robot's betrayal of Dr. Robotnik, the doctor apparently never found out about this.[10]

Sonic Battle[]

Main article: Chaos Gamma

In Sonic Battle, Dr. Robotnik, now carrying the alias "Eggman", was experimenting on using Chaos Emerald shards on robot cores to power his machines. As such, he used old, spare parts as guinea pigs for this project.[11] Amongst these were Gamma's destroyed remains, which the doctor had recovered to build a prototype:[9] Chaos Gamma, nicknamed that way to distinguish it from the previous version.

Other game appearances[]

Sonic Shuffle[]

Gamma is one of the secret characters in Sonic Shuffle, where the game's description says he returned "by the strange power of the dreams of Maginaryworld."[12] Like all players he holds a unique playing ability. If he plays a 4, 5, or 6 cards, he will change into wheel mode which will negate the effects of minus ring spaces. If he plays a special card during a battle, two roulettes will spin, and the sum of the two numbers will equal the damage done to an enemy. Gamma is unlocked after obtaining the final image in Amy's room.

Sonic Heroes[]

In Sonic Heroes, Gamma is mentioned whenever Omega gets an E-Rank, where he expresses his own "inferiority" compared to Gamma and Beta.

Sonic Rivals[]

In Sonic Rivals, Gamma makes an appearance as the 135th collectible card in the game.

Super Smash Bros. series[]

Super Smash Bros. Brawl[]

In Super Smash Bros. Brawl, Gamma appears as a Sticker:

Image Name Page ID Area of Effect Effect User
Brawl Sticker E-102 Gamma (Sonic Adventure Director's Cut)
E-102 Gamma (Sonic Adventure Director's Cut) 275 687 Flame Attack +11 Everyone

Super Smash Bros. Ultimate[]

In Super Smash Bros. Ultimate, Gamma appears as a Primary Spirit with the following characteristics:

Image Stat statistics Spirit Battle
Base Max Enemy Fighter(s) Enemy Power Stage Battle conditions
E102gamma Power: 953
Attack: 453
Defense: 500
Power: 4,768
Attack: 2,265
Defense: 2,503
R.O.B. (120 HP) 1,700 Frigate Orpheon Rule(s): N/A
  • Stamina battle
  • The enemy's shooting items have increased power
  • The enemy starts the battle with a Ray Gun
Name Type Class Music Acquisition
Gamma Grab ★ (Novice) "Open Your Heart"
  • Battle via Spirit Board
  • Purchase from the Vault Shop for 500G
No. Slots Ability
784 1 N/A

Sonic & All-Stars Racing Transformed[]

In Sonic & All-Stars Racing Transformed, Gamma appears as an icon on the game's "Blast Processing" Sticker.

Sonic Forces: Speed Battle[]

In Sonic Forces: Speed Battle, Gamma is one of the playable characters, who was added to the game's roster in the version 4.6.0 update. He has the following gameplay characteristics:

Image Rarity Stats Items
Projectile Boost Trap
SFSB Gamma
Super Rare

Speed: 8/10

Acceleration: 8/10

Strength: 6/10

SFSB Missile Launch
Missile Launch
Electro Boost
SFSB Laser Blaster
Laser Blaster


With a steel heart inside a steel body, I'm a high-tech assault machine. Watch out for the laser rifle on my right arm!

— E-102 Gamma's calling card, Sonic Adventure

Unlike the other models of the E-100 Series, Gamma possessed free will as a result of a flaw in his programming.[7] Despite this, Gamma initially served as just another mindless robot who would blindly obey Dr. Robotnik without question, due to seeing the doctor as a "master" and deeming a master's orders as "absolute".[3][4] As such, he would see his creator as an ally, and his adversaries, namely Sonic, as "enemies".[13][4] However, this mentality also meant that he would do certain tasks without knowing why;[14] despite his position, Gamma was an actually innocent individual who did not mean any harm, and would be deeply saddened inside whenever he was the cause of someone else's misfortune.[2] Described as having "a steel heart inside a steel body",[5] he would also be conflicted by thoughts of his creation and loyalty to Robotnik throughout his short life, questioning what he was supposed to do and whether his actions were okay,[4] even immediately after his creation.[15] As the doctor did not give Gamma "feelings", the robot would also fail to understand why a person would want to protect something or someone that was useless to them.[14]

Encounters with Amy Rose and witnessing Dr. Robotnik's wrath led to Gamma abandoning the doctor and erasing his master registration from his memory. Since then, he would view his creator as his "enemy" and the other E-Series robots as his "friends" and "Dr. Robotnik's evil machines" that he had to rescue.[16][17] It should be noted that even after this, Gamma still held a rather regimented attitude and devotion to his mission.

Stereotypical of most robots, Gamma tended to use technical sesquipedalian words. A common example of this included saying "Does not compute" or "Data unavailable" when he did not know something.[14] It should be noted, though, that he was still capable of casual human speech, which was shown when he had short conversations with Amy.[14] He could also make assumptions based on the data he had collected.[18]

Powers and abilities[]

E-102 Gamma was designed for battle. As part of the E-Series, he was also a very advanced robot that was developed to advance weaponry.[19]

Sonic Adventure DX Gamma gameplay

Gamma using his machine gun in combat, from Sonic Adventure DX: Director's Cut.

Being a gunner robot,[20] Gamma wielded a single 15.5cm guided rapid-fire[1] laser rifle[5] that could accurately fire homing missiles in rapid succession. Additionally, E-102 was equipped with an infrared alignment laser that allowed him to lock-on to multiple targets at once.[21] He also boasted high combat skills; once he was able to hold his own against Sonic. Most noticeably though, he could defeat E-101 Beta, who was already an even more advanced robot,[22] as well as his successor, on his own.

Gamma had a variety of "modes" to change his body frame to suit a situation. In his default mode, he could simply walk at a rather slow pace. By activating "Drive Mode", he would crouch down to roll on a set of wheels behind his feet to increase his speed. Another mode included "Water Mode", in which he would float indefinitely over water by deploying a fan on his abdomen.[1]


In addition to his normal armament, Gamma could also equip different devices to improve his abilities. These included the Laser Blaster, which increased his shooting range; and the Jet Booster, which gave him the ability to hover over pits.


Dr. Robotnik[]


Gamma and Dr. Robotnik.

As his creator and the first person he saw upon activation, Gamma exhibited a strong sense of loyalty and devotion towards Dr. Robotnik. Because of his programming, Gamma originally obeyed Robotnik every time and did his missions without questions. However, after a series of events, Gamma turned against Robotnik without the doctor's consent, having considered him to be an "enemy", and removed any data that made him obedient to the doctor in his programming.

Amy Rose[]

You have feelings of something you know nothing about.

— E-102 Gamma, Sonic Adventure
Gamma and Amy

Gamma and Amy.

Amy Rose formed a large bond with Gamma that greatly defined his fate. The two first met at the prison cell of the Egg Carrier, where Gamma tried to convince Amy to give him Birdie, though with no success. After having a closer look of Birdie, however, E-102 liberated her from her cell, telling her to go away, much to her surprise. The two later met when Gamma was fighting Sonic, a battle Amy stopped. After this event, Amy told Gamma to abandon Robotnik. Following the fall of the Egg Carrier, Gamma followed Amy's advice and turned on against his master.

E-100 Series[]






Main article: E-1000

E-1000 was a mass-produced robot model deployed by Dr. Eggman during the Space Colony ARK incident. However, the E-1000 robots were far less armed, armored, and sentient compared to Gamma.

Chaos Gamma[]

Main article: Chaos Gamma
Chaos Gamma

Chaos Gamma, from Sonic Battle.

E-102 Gamma, also known as Chaos Gamma, was a successor of Gamma created by Dr. Eggman during the Emerl incident. Compared to the original Gamma, this model possessed several more weapons, such as a grenade launcher and an electric dagger. The robot made numerous attempts to capture Emerl for his master and held a Chaos Emerald shard in its body at one point in an attempt to strengthen it.

In other media[]

Books and comics[]

Archie Comics[]

Gamma Archie Profile

Gamma, from Sonic Universe #3.

In the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics, Gamma was the second unit in the E-100 Series robotic group created by Dr. Robotnik. Gamma was one of the first E-100 Series robots created during Robotnik's campaign to harness the power of Chaos. Due to an encounter with Amy Rose and her Flicky friend however, Gamma gained a consciousness. Gamma then went rouge and waged war on the Eggman Empire. After over a year spent fighting alone, Gamma was offered to join Guardian Units of the Nation, but was hunted down and destroyed by E-123 Omega. However, he managed to upload his "free will" code into Omega's programming to continue his dream.

After the Super Genesis Wave re-wrote history, Gamma became virtually indistinguishable from his video game counterpart.


Sonic X[]

Main article: E-102 Gamma (Sonic X)
Ep27 E-102 Gamma Sonic X 2

E-102 Gamma, from "Pure Chaos".

In Sonic X, Gamma was the second robot of the E-100 Series line created by Dr. Eggman in an attempt to harness Chaos' energy to destroy Station Square. Like his video game counterpart, Gamma turned against his master following an encounter with Amy and Lily and began a mission to hack his brothers' systems to make them turn against the doctor too. However, this did not work on Beta, who attacked Gamma. After trying to reason with him, with little success, Gamma clashed with him, fatally damaging them both and "freeing" their animal batteries. As they collapsed and exploded, their hands grasped each other's, as a touching final symbol of their unity. During this event, Amy saw the two being destroyed and cried, as the birds inside of the robots were freed and acknowledged as siblings, echoing the relationship between Gamma and Beta.


Ge gamma plush

The E-102 Gamma plush, by Great Eastern Entertainment.

In the Sonic Adventure plush-line by Sega Prize!, E-102 Gamma has his own extremely rare plush and It is infamously known for being very fragile and easy to rip. In Wave 2 of the ReSaurus Sonic Adventure toy line, Gamma got his own action figure and a Ring as a accessory. It also has a base with some Gamma art on it to support it and hold up the Ring accessory. Additionally, Toy Island produced a unreleased E-102 Gamma bendy action figure for their Sonic Adventure bendy figures toy-line. It is unknown why it was cancelled.

On the 27th of February 2022, Great Eastern Entertainment released an 12" E-102 Gamma plush for their Sonic the Hedgehog plushies.


"How can I serve you, Dr. Robotnik?"
—E-102 Gamma, Sonic Adventure
"Resistance is futile!"
—E-102 Gamma buring battle against Sonic or Tails, Sonic Adventure

Theme songs[]


  • E-102 Gamma can be converted into a mathematical formula (e - (102 * Euler-Mascheroni Constant)) which equals -56.1577159915.
  • Unless Gamma manages to hit a wall corner and glitch downward, he cannot take a step into any water environments. Attempting to do so will automatically transform him into his hover mode until he is moved to dry land, and he will instantly change into his wheeled mode upon landing.
  • The physics of Gamma's Mode Changes change should he be holding something when he transforms. If he changes into his wheeled mode while carrying an item, he will not announce the change, and he will transform back into his default mode upon stopping. Should he change into his helicopter mode while carrying an item, his physics change to become more floating, and he can overcome barriers his normal helicopter mode cannot.
  • An odd effect takes place in Gamma's Adventure Mode in Sonic Adventure upon completing his story, creating a consistent night-time effect in the Adventure Fields. This also happens in Sonic Adventure DX: Director's Cut, but resets upon entering Mission Mode.
  • Gamma is the only playable character in Sonic Adventure not to appear in the end story of that game, although the pink bird that powered him is present.
  • Gamma is the only playable character who never encountered Chaos in Sonic Adventure.
  • Although Gamma is the tallest playable character in the franchise, he is considerably lighter than E-123 Omega.
  • Gamma is the only playable character in Sonic Adventure DX and all future ports who cannot attack Chao in the Chao Gardens, although he was able to do so in the Dreamcast version by locking onto them and firing at them.
  • Gamma is one of only two characters to have Sonic Channel artwork identical to their first render, the other being E-123 Omega.
    • Coincidentally, both characters are robots who were created by Dr. Eggman and then turned against him.
  • Gamma is the only playable character who did not receive an updated model with a higher polycount in Sonic Adventure DX: Director's Cut, nor did he receive updated textures.
  • In the original Japanese release of Sonic Adventure, Gamma was a completely silent character during gameplay, only speaking in cutscenes and during his rival battle. This was changed in the international release and all subsequent versions.
  • Gamma's phrase "Resistance is futile!" is a reference to the Borg from Star Trek.
  • Gamma was originally intended to be in Sonic Heroes in a team with Big and Chaos.[23] This is likely why Chaos and Gamma were in Sonic Battle, over Omega or the Chaotix. It was mentioned that even though Gamma died in Sonic Adventure, his shell still remained and his inner part could have been replaced.[24] In fact, Gamma is the only playable character from Sonic Adventure not to return in Heroes.
  • In Sonic Forces: Speed Battle, Gamma has the unspoken ability to float in the air for a few seconds when jumping.
  • Sonic, Tails, and Amy most likely recalled hearing his name from when he was summoned by Dr. Eggman, to battle with Sonic and Tails. How Knuckles knows Gamma's name is unknown.


  1. Could use this move in Sonic Forces: Speed Battle.


  1. 1.0 1.1 1.2 1.3 1.4 Sonic Channel (Japanese). Characters: Gamma. Sega. Archived from the original on 26 May 2019. Retrieved on 3 July 2015.
  2. 2.0 2.1 2.2 "E-102 'γ'". Sonic Adventure Stylebook. p. 46. "Profile - A marksman robot of Robotnik's devise. An innocent creature trying to avoid demise. This poor little thing really means no harm. He's so sad inside when he causes alarm!"
  3. 3.0 3.1 Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Cutscene: Story Screen before entering the room with Beta (Gamma's story). "E-102. Code name Gamma. I am a robot. I was created by Dr. Robotnik. Dr. Robotnik is my master. My master's orders are absolute."
  4. 4.0 4.1 4.2 4.3 4.4 ZedArchive (10 April 2022). Sonic Adventure Production Presentation At Tokyo International Forum (1998) [ENGLISH CC] (Japanese). YouTube. Retrieved on 7 October 2022.
  5. 5.0 5.1 5.2 E-102 γ's calling card.
  6. 6.0 6.1 "All Star Cast". Sonic Adventure Tokyo International Forum Unveiling Booklet. 22 August 1998. p. 9.
  7. 7.0 7.1 Promotional profile from Sonic Adventure.
  8. Retro Game staff (28 December 2018). "The Making Of: Sonic Adventure". Retro Gamer. Archived from the original.
  9. 9.0 9.1 ガンマ (Japanese). ナ力マだ!. Sonic Team. "かつて一羽の小鳥を助けるために記憶を失ったロボット。Dr.エッグマンの試作品のため動作は遅いが、高い攻撃力と一発逆転ができる必殺ワザをもつ! [A robot that once lost its memory to help a small bird. It's a prototype of Dr. Eggman, so it's slow, but it has a high attack power and a deadly trick that can be reversed in one shot!]"
  10. Sega (21 October 2016). Act:017 ゼータ先輩の教訓. Sonic Channel. Retrieved on 21 May 2022.
  11. Sonic Team (27 February 2004). Sonic Battle. Game Boy Advance. Sega. Area/level: Central City (Knuckles' Episode). "Rouge: Dr. Eggman has been experimenting with using 'Chaos Emeralds' on robot cores. He used a bunch of old parts to create guinea pigs for his experiments. That robot's probably just has parts that you recognize."
  12. Sonic's Gallery, photo 37: "Gamma is back, by the strange power of the dreams of Maginaryworld."
  13. Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Cutscene: Final Egg (Gamma's story). "Blue hedgehog... enemy"
  14. 14.0 14.1 14.2 14.3 Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Area/level: Egg Carrier (Gamma's story). "Amy: Go away! / Gamma: Give me the bird. / Amy: No way! / Gamma: Resistance is futile: give me the bird! / Amy: I said NO! / Gamma: Why not? / Amy: None of your business why not. I want to know why you want it. / Gamma: Data unavailable. / Amy: You don't even know? I'd bet you be mean to him, you bully! Why not help us out instead? Don't you know how bad I feel? / Gamma: Does not compute. Why try to save what is useless to you? Does not compute. / Amy: I feel sorry for you! Eggman failed to give you feelings."
  15. Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Cutscene: Story Screen before playing Final Egg (Gamma's story). "E-102. Code name Gamma. That is what that man said my name is. That man is Dr. Robotnik. What am I? What should I do? Does not compute..."
  16. Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Area/level: Mystic Ruins (Gamma's story). "Gamma: Dr. Robotnik... Enemy... Master registration... Deleted. E-Series... Friends... Must save..."
  17. Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Cutscene: Story Screen before playing Windy Valley (Gamma's story). "I'm E-102, Gamma. I have deleted Dr. Robotnik from my registry as my master. I will act at my own discretion from now on. I will destroy all of Dr. Robotnik's evil machines and rescue the animals. My mission is to save my fellow E-Series friends! Search commencing."
  18. Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Cutscene: Story Screen after playing Red Mountain (Gamma's story). "I'm E-102, Gamma. [...] I rescued E-104 Epsilon in the Red Mountain. E-101 Beta and E-105 Zeta location unknown. Perhaps they are on the Egg Carrier?"
  19. "Dr. Eggman in... My Greatest Invention". Sonic the Hedgehog: Rival Edition. Tomy. 2017.
  20. Sonic Adventure (Dreamcast) United States instruction booklet, pg. 26.
  21. ZedArchive (10 April 2022). Sonic Adventure Production Presentation At Tokyo International Forum (1998) [ENGLISH CC] (Japanese). YouTube. Retrieved on 7 October 2022.
  22. Sonic Team (23 December 1998). Sonic Adventure. Dreamcast. Sega. Area/level: Mystic Ruins (Gamma's story). "Dr. Robotnik: Enter, Gamma! You are not as advanced as Beta is, but you'll do fine."
  23. Shiro Maekawa (@mizuhano) on Twitter (Japanese). Twitter (26 April 2018).
  24. Shiro Maekawa (@mizuhano) on Twitter (Japanese). Twitter (26 April 2018).