With Jim Carrey announcing his upcoming retirement from acting, Sonic The Hedgehog 3 is in need of a new villain after his departure. Golden Globe-winning comedy actor Jim Carrey enjoyed a new surge of popularity for his performance as the nefarious Dr. Ivo "Eggman" Robotnik in Sonic The Hedgehog and Sonic The Hedgehog 2. However, Carrey has said that he intends to retire from the film industry in the near future.
At the conclusion of Sonic The Hedgehog 2, Sonic defeats both Dr. Robotnik and a giant robot of his creation with the aid of the seven Master Emerald shards. Robotnik's robot is destroyed with him still inside, causing the mad scientist to be lost in the mech's remains. Although there could be a chance that he survived the robot's destruction, due to Carrey's announced retirement, it would not come as a surprise if Robotnik doesn't return.
Now that Sonic The Hedgehog 3 is currently in development, it appears that Carrey's Eggman will not be present, thus leaving a space open for a new villain to take his place. While disappointing, it does open the door in regard to introducing an entirely new villain to battle Sonic and his new friends. Here's everyone who could fill the villain role in Sonic the Hedgehog 3.
Agent Stone
Agent Stone is Dr. Robotnik's personal assistant who is known and deeply appreciated for both his devotedness to his mentor, as well as his knack for brewing the perfect latte. He should not be underestimated, as Robotnik himself has stated that Stone has a genius-level intellect, which allows him to keep up with the mad doctor as he builds his high-tech inventions. Much like Eggman, Stone is inherently evil, incredibly ruthless, and highly manipulative. During his time at the Mean Bean Coffee Café, he uses these skills to his advantage, resulting in him sailing through the ranks of the café, taking partial control of it in the process. However, that is nothing compared to how he utilized underhanded tactics to get rid of other employees that he disagreed with, not to mention framing his manager for laundering money within his first seven days of employment.
As of the ending of Sonic the Hedgehog 2, Stone is seen having infiltrated G.U.N. (Guardian Unit of Nations) disguised as one of their soldiers. This means he will most likely remain at large when the next film releases. It could be likely that Agent Stone will want revenge against Sonic for his boss' defeat, most likely putting his intelligence to work by taking up Robotnik's role as mad scientist and inventor. The only rebuttal that can be said about Stone's capacity for villainy is that, despite his potential, he is much too loyal to Robotnik and prefers to not step out from under his shadow. However, he could possibly be the one responsible for unleashing the film's true villain.
Metal Sonic
Any fan of the Fastest Thing Alive should know this particular robot. Being one of Sonic's very first rivals, Metal Sonic has the potential of being the next film's big bad, especially since his story is closely tied with Dr. Robotnik's. Within the Sonic mythos, Metal was a robotic duplicate of Sonic constructed by Eggman for the sole purpose of killing the real Sonic. In order to perform such an act, Robotnik had to build and program Metal Sonic to be better than the Sonic in every way, shape, and form. Metal Sonic's metallic frame is incredibly durable, the miniature turbine embedded in his chest can help him reach and even surpass Sonic's running speed, and, unlike the rest of Eggman's "Badnik" robots, he is given an incredibly powerful processor unit for a brain, as well as artificial intelligence, which gives him the drive to prove that he is truly superior to Sonic, no matter the cost. Essentially, Metal is Eggman's crowning achievement and greatest creation to date.
Perhaps Metal's introduction into the film franchise could stem from how Eggman originally utilized Sonic's energized quills as power sources for his machines and vehicles. It could be possible that the doctor was working on a new passion project that he started between the first and second films, revealed to be Metal Sonic, who is then activated and unleashed on the world to cause mayhem and kill Sonic. With a villain as dangerous as Metal Sonic, it could give the audience fantastic action sequences, as well as pay a tribute to Jim Carrey's character because of their intertwined origins.
Shadow The Hedgehog
In the mid-credits scene of Sonic 2, a very prominent figure in the Sonic universe is introduced: the one and only Shadow the Hedgehog. Aside from Metal Sonic, Shadow is Sonic's biggest rival to date, but their rivalry is one of different circumstances. Rather than being an adversary who is primarily focused on besting and defeating his opponent, Shadow is more an antihero than a villain, an entity that performs seemingly heroic deeds by means of unorthodox and frowned-upon tactics. Essentially, anyone who Shadow condemns as foolish or deserving of retribution, villains and heroes alike, he "handles." This mindset and behavior frequently put him at odds with Sonic, his opposite, which can most certainly happen in the next film.
However morally gray Shadow can be, though, more often than not his and Sonic's goals become the same, making them become uneasy allies until the two eventually team up permanently. While this is usually the case for Shadow, such an instance has already been seen in Sonic 2 with the character of Knuckles The Echidna. With Shadow confirmed to be in the next film, it will be interesting to see how he interacts with Sonic and the others in a manner that does not mirror Knuckles' arc.
Black Doom
While not that many people are familiar with the character of Black Doom, his tale is tied with Shadow's backstory. As seen in his mid-credits scene, Shadow is restrained in a stasis tube located in a laboratory belonging to Dr. Robotnik, labeled as Project: Shadow. However, it is said that the project dates back approximately 50 years before the events of the first film. If Sonic 3 is taking any and all source material into account, then this could be a reference to Shadow's solo game Shadow The Hedgehog, which reveals that Shadow is the creation of Eggman's grandfather, Gerald Robotnik, who sought to synthesize what he refers to as "the ultimate lifeform."
In order to have Project: Shadow fully realized, Gerald was assisted by Black Doom, the leader of an alien species known as the Black Arms. Doom offers some of his own blood to Gerald in order to create Shadow, which leads to the success of the Project. However, Black Doom's assistance came at a cost. In 50 years' time, Gerald was to deliver to Doom the Chaos Emeralds, a time period that is the same as the movie. If Shadow is to appear in the next film, there could be a strong chance that Black Doom might show up to reign as the new villain.
Chaos
One major part of the Sonic mythos introduced in Sonic the Hedgehog 2 is the Master Emerald. As shown in the film, the Master Emerald is the combination of the seven Chaos Emeralds. It is a powerful artifact, one that Eggman covets, Knuckles wishes to have returned, and Sonic prefers to keep out of both of their hands. Its history, however, is much more complex than that, but it does play into Knuckles' backstory. The Master Emerald initially was a completely different entity from the Chaos Emeralds, and it was protected by the Echidna Tribe, Knuckles' family. Before Knuckles became the de facto guardian of the Emerald (even before the Echidna Tribe stepped into the picture), it was protected by a god-like being known as Chaos, a mutant with a body of concentrated energy.
Originally a peaceful creature, Chaos' purpose was to protect the Master Emerald. After the Echidna Tribe set up shop, Chaos went into a great rage and vowed to destroy the world. As a result, the Echidnas utilized the Master Emerald's power to seal Chaos inside. If the Master Emerald is now a prominent item in Sonic The Hedgehog 3, this could lead to a possible (or even inevitable) release of the vengeful Chaos upon the world, and he could surely be a major force to be reckoned with.