This year's adaptation of the popular video game property Sonic the Hedgehog proved to be a huge financial success, with critics praising the performances and animation. Following a post credits scene that introduces beloved sidekick Tails, fans have since been wondering whether any other familiar characters will make it into Sonic the Hedgehog 2, with sources now claiming that fan-favorite red echidna, Knuckles, will feature heavily in the sequel.

Many have speculated that Knuckles would be introduced in a Sonic the Hedgehog 2 cameo, similar to that of Tails in the first movie, but sources have now indicated that he will have a "relevant role" in the follow-up and that the character's appearance "will be larger than a cameo."

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It is also being reported that Knuckles will "stay true to his video game incarnation", meaning that he will be able to both glide and climb walls just like the in the video game. His personality has been described as "serious in nature, but still gullible at times," with the studio currently in the casting process for the voice of Knuckles.

Alongside the Knuckles news, it has also been reported that director Jeff Fowler will be back to helm the video game sequel, along with screenwriters Pat Casey and Josh Miller, and that the movie is looking to start production next May. The same sources have even revealed that Sonic the Hedgehog 2 is looking to add another human character named Randall, who will specifically not interact with the titular spiny mammal, and that production is looking to add an A-list cameo to proceedings, with Samuel L. Jackson and Chris Rock reportedly being considered.

Knuckles remains one of the most popular characters in Sonic lore and, with this in mind, it may seem odd that he was not included in the first movie. Director Jeff Fowler though has already explained why the decision was made to leave him out. "For this first film, we really were just looking at the 1991 game and just see where it all started and just keep it simple," Fowler said earlier this year. "Just really try to nail Sonic and Robotnik and just set up their rivalry because you don't... I mean, I love... There's a lot of great characters in the Sonic universe, but it's the most important thing is just to get Sonic set up and just tell a little bit of an origin story with him, and just do it in a way that really makes everyone fall in love with him as a character and just be rooting for more. And then, if all that goes well, then we can kind of open it up and bring in some of these other characters that fans know and love. And yeah, I mean, no one's more excited than me to have that opportunity."

Sonic the Hedgehog finds the superfast, blue-colored hedgehog Sonic, as he tries to navigate the complexities of life on Earth with his newfound best friend -- a human named Tom Wachowski. They must soon join forces to prevent the evil Dr. Robotnik from capturing Sonic and using his powers for world domination. The ending of Sonic the Hedgehog does hint at a potential sequel and the direction it may go in, as well as giving audiences a look at another beloved Sonic sidekick, Tails, in a post-credits scene. Directed by Jeff Fowler, Sonic the Hedgehog stars Ben Schwartz as Sonic and Jim Carrey as Dr. Robotnik, with James Marsden, Neal McDonald, Tika Sumpter, Adam Pally, and Natasha Rothwell. This comes to us from The Illuminerdi.