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Could this be The Prototype of The Ultimate Life Form that was supposed to be encapsulated?

Knuckles the Echidna, Sonic Adventure 2

The Biolizard (バイオリザード Baiorizādo?) is a character that appears in the Sonic the Hedgehog series. He was the first Prototype of the Ultimate Life Form (究極生命体プロトタイプ Kyūkyoku Seimeitai Purototaipu?) created by Gerald Robotnik during Project Shadow, but was far too dangerous and flawed. After the final version of the ultimate life form, Shadow the Hedgehog, was created, the Biolizard was encapsulated by G.U.N. Fifty years later, the creature resurfaced and tried to destroy the earth, but was ultimately defeated by the combined efforts of Sonic and his friends.


The Biolizard was a colossal and grotesque lizard-like beast, easily over two hundred feet long from the tip of his nose to end tip of his tail, about one hundred feet wide, and about sixty feet tall at the tallest point on his back. He had orange flame skin with a dark gray underbelly, and possessed a long neck, a flat and almost round torso with gill-like flaps on the sides, and a thick tail. He also had two stubby and thick forelegs, each with three thick toes on a foot indistinguishable from the leg, and four short flippers on the rear. Where his rear legs would be, he instead had stub legs with no defined feet. Additionally, he had a large and pale mouth with black lips, where he had numerous small sharp teeth, and four yellow spikes on the lower jaw. On his neck, back, hind quarters and tail, the Biolizard had yellow patches of skin.

The Biolizard had several robotic implants. His eyes were like gun-turrets, and he had a large disk-shaped machinery with a red orb in the middle on his back which was his life support system. He also had several cables on his back and a set of green cables on his jaw joints connecting with his life support system, along with a stump of green cable on his forehead. He also seemed to have vents near the foot of his neck.



The creation of the Biolizard was conceived when "Project Shadow" was launched by the President of the United Federation. This government project, led by Professor Gerald Robotnik, was intended to create an "ultimate life form" for humanity to research immortality with and create an "immortality formula" for war.[3] However, Gerald's own motives for creating this creature was to use the immortality research from the project to develop a cure for a fatal disease afflicting his granddaughter, Maria Robotnik.[4]

The Biolizard was created by Gerald onboard the Space Colony ARK as the prototype for the ultimate life form and was modeled after a lizard.[4] At 12:30am on 27 January, the Biolizard was successfully brought to life, with his eternal engine and Chaos Control-inducing organ working normally. However, because the measurements of the experiment were higher than expected, the Biolizard was moved to the Central Dome for further tests.[5]

As he grew, the Biolizard showed many of the researchers' desired traits, including self-restoration, regeneration and self-reproduction.[4] However he required a life support system fueled by Chaos Drives to sustain himself. Other flaws also became noticeable over time: besides having an unexpected and exponentially fast growth rate (growing to be 2.7m long and weighting 350 kg in just a couple of days)[1] that strained his vital organs' control parts, the Biolizard possessed a mind of a primitive animal and was too weak to walk at that time. As such, it was required to keep him under observation.[1] His abilities also exceeded all expectations.[4] Eventually, the Biolizard evolved to become so unruly that the researchers had trouble controlling him.[4] The Biolizard was later abandoned when Gerald produced a more advanced being with Black Doom's DNA: Shadow the Hedgehog.

Eventually, the private information about the Biolizard's violence leaked to G.U.N., supposedly by the internal staff who had begun worrying about Project Shadow and their own safety after witnessing the Biolizard going out of control. This made the government deem Gerald's work a danger to humanity. When G.U.N. invaded the ARK to eliminate everything related to Project Shadow, the Biolizard was found in the deepest part of the ARK and encapsulated.[4] The beast did not go down without a fight though, and he destroyed almost the entire group of G.U.N. soldiers before being subdued. The Biolizard presumably was programmed to awake from suspended animation by a by-that-point insane Gerald Robotnik if intruders came near the Cannon Core as a final line of defense in case anyone tried to prevent the ARK from crashing.

Sonic Adventure 2[]

Clash of the Ultimate Life Forms

The Biolizard facing Shadow, from Sonic Adventure 2.

The Biolizard was first alluded to by Rouge after tricking Eggman into allowing her to access the mainframe of the ARK and discovering files pertaining to the Ultimate Lifeform.[6] She later showed the files to Shadow as insurance after he stumbled upon her attempted theft of the Chaos Emeralds, as well as strongly implying that his claim of being the Ultimate Lifeform was false at best.[7]

In Sonic Adventure 2, the Biolizard had remained in suspended animation for over fifty years until Dr. Eggman unknowingly initiated Gerald's program that sent the ARK falling towards earth when trying to use the fully charged Eclipse Cannon. When Sonic and Knuckles came to the Cannon's Core to stop the ARK by deactivating the Chaos Emeralds, the Biolizard awakened and appeared in front of them, blocking their path to the Emeralds. However, Shadow then arrived to keep him at bay. Despite his best attempts, the Biolizard was defeated when Shadow managed to damage his life support system.

After Knuckles stopped the Chaos Emeralds, the Biolizard made a fast recovery and used Chaos Control to teleport outside of the ARK and fused with the space colony himself, becoming the Finalhazard, to keep it on its collision course. Shortly after, he fought both Super Sonic and Super Shadow, but was defeated and destroyed as the ARK entered the planet's atmosphere.

Shadow the Hedgehog[]

Dolphin 2016-06-17 15-48-33-919

A flashback of the Biolizard's death, from Shadow the Hedgehog.

In Shadow the Hedgehog, the Biolizard would appear during one of Shadow's flashbacks, when he remembered his apparent death after defeating him.

Sonic X Shadow Generations[]

Shadow Generations BioLizard

Shadow confronts the Biolizard, from Sonic X Shadow Generations.

In Sonic X Shadow Generations, the Biolizard is set to appear as a boss in the "Shadow Generations" story.[8]

Other game appearances[]

Sonic Rivals 2[]

In Sonic Rivals 2, the Biolizard appears on a collectible card:

Image Card Number Card Challenge Unlocked
Sonic Rivals 2 - Card Collection 87 87 Biolizard Win Knuckles Cup in Single Player Knuckles' Armor Suit

Sonic and the Black Knight[]

In Sonic and the Black Knight. when playing the "Dragon Slayer" mission in Dragon's Lair, Sonic sometimes references the Biolizard when facing the Earth Dragon.

Sonic Generations (Nintendo 3DS)[]

In the Nintendo 3DS version of Sonic Generations, when Dr. Eggman used the Time Eater in an attempt to alter Sonic's past, Sonic faced and defeated the Biolizard during his trip back in time to when the creature was set loose in Cannon's Core.


Unlike Shadow, the Biolizard was more akin to a primitive animal, possessing a low intelligence and learning ability.[1] He was extremely unruly, reckless and hostile, causing so many troubles that the researchers onboard the ARK feared for their lives.[4] He was also sensitive to temperature and humidity changes, and would react violently when possessing the power of the Chaos Emeralds.[4]

Powers and abilities[]

As the prototype of the ultimate life form, which was aimed to create immortality, the Biolizard has many of the abilities attributed to the desired end-product. However, the various experiments had severely weakened him, and he required a life support system to stay alive.

The Biolizard possessed a regenerative healing factor which let him restore and regenerate himself quickly when injured. He could as well asexually self-reproduce himself by creating pinks eggs seemingly out of nowhere.[4] The surface of the Biolizard's skin was as well designed to absorb all outside attacks. With his life support system aiding him, the Biolizard's skin could resist attacks to such a degree that any blow would just bounce off it, making him virtually invulnerable.[9] Additionally, the Biolizard was noted to possess a strong neck and tail.[1] While he was also not able to walk at one point, he was a very fast crawler, being able to keep up with both Sonic and Shadow as they circled around him by crawling.

Sonic2app 2015-11-19 22-07-29-355

The Biolizard using Chaos Control, from Sonic Adventure 2.

The Biolizard could project dark energy balls from his mouth and direct them in curved formations. He also had the ability to create a magnetic field, which he could use to either lift opponents helplessly into midair or move and repulse objects, allowing him to turn his eggs into projectiles or arrange them in different formations. By harnessing energy from the Chaos Emeralds, the Biolizard was also capable of both making himself stronger[10] and performing Chaos Control by use of a special organ.[5]


Main article: Finalhazard

By merging with the Space Colony ARK at the tip of the Eclipse Cannon, the Biolizard could transform into the Finalhazard. In this form, he could harness the energies of both the ARK and the Chaos Emeralds, making him strong enough to fight on par with both Super Sonic and Super Shadow. Additionally, he could fire energy beams, and his magnetism manipulation was more refined. However, because his life support system had been demolished, the harsh conditions of space would create vulnerable spots on his body.


The Biolizard's main weakness was his own flawed design. He relied heavily on the power of his life support system and destroying it would leave him vulnerable. He also appeared to have low stamina, as he would quickly exhaust himself with his attacks.



In other media[]


Sonic X[]

Main article: Bio Lizard (Sonic X)

The Bio Lizard, from "Showdown in Space".

The Biolizard also appears in the Sonic X anime series, where it is named the Bio Lizard and its role parallels the one it plays in Sonic Adventure 2. Like in the games, he was created onboard by Professor Gerald, but was sealed away when the military shut down the ARK. He later fought Sonic and Shadow in an attempt to destroy Earth.

When Gerald's doomsday plans were put into motion by having the Space Colony ARK collide with earth, the Bio Lizard tried to stop Sonic the Hedgehog and his allies, but was destroyed by Super Sonic and Super Shadow.

Books and comics[]

Archie Comics[]

Main article: Biolizard (Archie)
Biolizard Pre-SGW Archie profile

The Biolizard, from Sonic Universe #2.

In the Sonic the Hedgehog comic series and its spin-offs published by Archie Comics, the Biolizard appeared following the Sonic Adventure 2 comic adaption. However, it was not until Sonic Universe #2, which retold the story, that the Biolizard made a physical appearance.

Like in the games, the Biolizard was created by Professor Gerald, but was later attempted to destroy Mobius. When Sonic and Shadow tried to foil Gerald's plans, the Biolizard attempted to make the Space Colony ARK collide with the planet, but was defeated by Super Sonic and Super Shadow.

Theme songs[]


  • Though Sonic, Shadow, and Omochao all refer to the Biolizard with masculine pronouns,[10][11][9] his ability to asexually produce eggs could indicate that he is hermaphroditic, or otherwise does not conform to the biology of real-life lizards.
  • The Dreamcast version of Sonic Adventure 2 had glitches in the game that led to unavoidable deaths when fighting the Biolizard (such as landing in the water as opposed to on the platform).
  • When Biolizard uses Chaos Control to become Finalhazard, the roars are heavily edited screams of Sonic and Shadow.[12]
  • When Biolizard summons pink eggs and begins to levitate Shadow, the roar used is the same roar used for Perfect Chaos in Sonic Adventure, but with a different pitch. In the Nintendo 3DS version of Sonic Generations, Biolizard 's roar is now reused from Dark Gaia Phoenix's from Sonic Unleashed.
  • After defeating the Biolizard in the Nintendo 3DS version of Sonic Generations, the following cutscene shows Sonic saying he fought him before. Technically, Sonic did not fight the Biolizard in his normal form (he was fought by Shadow) but Sonic did fight him when he transformed into the Finalhazard.
  • As of Sonic X Shadow Generations, the Biolizard is the only boss besides the Rival bosses and the Time Eater that appears in both the console and the 3DS port of the game.


  1. 1.0 1.1 1.2 1.3 1.4 Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Cutscene: Cutscene 27. "The 23rd "Project Shadows" report - Note: Pr. Gerald pointed out that the growth speed of the first prototype is getting faster. The current body length is 2.7m, and the current weight is 350kg. It's growing so fast in the last couple of days at an exponential level. Professor has requested that the control part of the life form's vital organs needs to be reinforced. We need to keep an eye on the prototype because the prototype is not strong enough to walk by itself, but it has a strong neck and a tail. The prototype is sensitive to the temperature and humidity changes, and its intelligence and learning ability level is still low. At this point, the prototype is still more like an animal."
  2. 2.0 2.1 Bio Lizard - Trying to clear the stage. Archived from the original on 9 August 2007. "When the Biolizard's health is almost depleted, it generates a magnetic field that suspends you. Avoid the airborne spinning eggs and land on its life-support system to attack. Keep moving with the eggs and so you can attack as soon as you land."
  3. Sonic Team (27 February 2004). Sonic Battle. Game Boy Advance. Sega. Area/Level: Gimme Shelter. "Rouge: 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."
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 "ソニックアドベンチャー2パーフェクトガイド" (in Japanese). 50年前の真実. Enterbrain. 10 October 2001. ISBN 978-4757706255.
  5. 5.0 5.1 Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Cutscene: Cutscene 27. "The 23rd "Project Shadows" report - Current status: 12:30A.M. on January 27th, we initiated the experiment to start Shadow's first prototype. The experiment was successful. The life form's external engine and the organ to start the Chaos control are working normally. However, the measurements of the experiment was higher than we expected, we will continue this experiment at the Central Dome from now on."
  6. Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Cutscene: Cutscene 27. Rouge: Hmm… tricking that old doctor is just too easy! Alright, it's time to get to work. The password is "MA-RI-A". Maria… hmmm? I've heard that name somewhere before. Oh well… [Rouge begins to run through large groupings of data on the monitor.] Rouge: This is it! Research Project Shadow, the Ultimate Life Form. Let's see now… What in the world is this? This can't be right! Just what is Shadow, anyway?
  7. Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Cutscene: Cutscene 32.
    Shadow the Hedgehog: You are one pathetic creature!
    Rouge the Bat: Hmmm, look who's talking? What about you?
    ["Fly In The Freedom" stops, and Rouge jumps down, holding a paper.]
    Rouge: Here are the results from the research project called the "Ultimate Life Form".
    [A picture of the Biolizard is on the paper.]
    Rouge: But, if this picture is of the real Ultimate Life Form ["Throw It All Away" starts playing] named, Shadow… then exactly who or what is standing in front of me?
    Rouge: Do you actually believe that you're the real Shadow?
    Shadow: No doubt!
    Rouge: Even your memories might not be real, you know?
    Shadow: Even if my memories are not real, it's still me, Shadow. And I will fulfill my promise to Maria, that's the only thing that matters to me now.
  8. SONIC X SHADOW GENERATIONS - Announce Trailer. YouTube. Sonic the Hedgehog (January 31, 2024). Retrieved on February 6, 2024.
  9. 9.0 9.1 Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Area/Level: Cannon's Core. "Omochao: The surfaces are designed to absorb attacks... it's invincible! As long as he's equipped with that red life support system, he's invincible!"
  10. 10.0 10.1 Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Area/Level: Finalhazard. "Super Sonic: Where does he get all that power? Is this the power of the Chaos Emeralds?"
  11. Sonic Team USA (23 June 2001). Sonic Adventure 2. Dreamcast. Sega. Area/Level: Finalhazard. "Super Shadow: He's very weak without his life support system. Aim for the red swelling area to damage him! You're our last hope!"
  12. SPEEPSHighway (6 March 2017). Sonic Adventure 2 - Unused Content & Trivia. YouTube.