This article contains spoilers for Sonic the Hedgehog 3.Sonic saves the day. Even if you keep drowning in Chemical Zone and throwing your old Sega Genesis controller across the room, you know that every Sonic the Hedgehog story ends with the Blue Blur triumphant and Robotnik defeated. Sonic the Hedgehog 3 is no different. By the end of his third big screen outing, Sonic (Ben Schwartz) befriends new antagonist Shadow the Hedgehog (Keanu Reeves) and stops Gerald Robotnik and his grandson Ivo Eggman Robotnik (both played by Jim Carrey, hammy as ever) from blowing up the world. Sonic even wins a footrace against Tails (Colleen OShaughnessey) and Knuckles (Idris Elba).But the post-credit scene shows that theres much more to the story, and to Sonics group of friends. The post-credit scene finds Sonic getting a bit too enthusiastic about his race and stopping in a New York forest. Before he can make his way back to Green Hills where his animal friends and human pals Tom (James Marsden) and Maddie (Tika Sumpter) wait, a new foe robotic foe arrives well, a legion of new robotic foes arrive: an army of Metal Sonics. Fortunately, Sonic gets an assist from a welcome face in the form of Amy Rose.These reveals will have the longtime Sonic fans in the audience cheering, but for those who left the franchise after playing Sonic and Knuckles, heres a primer.As Sonic himself points out, the mechanical assailant looks a lot like himwhich is exactly the point. Metal Sonic debuted in 1993s Sonic CD, an appropriately sci-fi villain to match the futuristic feel of playing a game on disc instead of a cartridge. Like most villains in the world of Sonic, Metal Sonic is a creation of Robotnik, who decides that the only way to defeat Sonic is to match him. Thus Metal Sonic has the same speed and skills as the hero, along with some extra bells and whistles.However, Metal Sonics greatest asset is his logical mind. Unlike his flesh and blood counterpart, Metal Sonic has no weaknesses for chili dogs, tiny captive animals, or his human pals. As a robot designed to improve upon the original in every way, Metal Sonic puts his mission before everything else, even turning against his maker from time to time after Robotnik keeps testing him in order to prove hes the One True Sonic the Hedgehog.Amy RoseAmys sudden appearance during the post-credit scene isnt an accident. Like Metal Sonic, Amy also joined the fictional world with Sonic CD, although shes been a bit more prominent in other media.As a pink hedgehog with a dress, Amy does fall into the standard trope of giving a male character a girl counterpart in the most superficial way possible. The giant mallet she wields, officially known as the Piko-Piko Hammer, does offset her some from her masculine counterpart, but too many Amy stories limited her roles to having a crush on Sonic and nagging when Sonic did something she didnt like. Even in Sonic CD, Amy was little more than a damsel in distress.However, Amy has begun to come into her own, especially in the past 10 years. In the pages of the Sonic the Hedgehog comics that fan-favorites Ian Flynn and Evan Stanley have been writing for IDW Publishing, Amys become something of a fortune teller, which adds depth to her positive attitude. Last years Amys 30th Anniversary Special, written by Flynn and penciled by Aaron Hammerstrom, serves as a perfect example, as Amys divination allows her to stop Metal Sonic and free her friends.Amy doesnt speak in the teaser, but well likely see a big name get cast in the role, someone on the level of Elba and Reeves. Could Anya Taylor-Joy make a jump from Nintendo to play another video game heroine?Fun as these reveals are, they may also re-contextualize Robotniks fate at the end of Sonic the Hedgehog 3. Robotnik seems to sacrifice himself, helping Shadow prevent the space station from crashing into the Earth. Which makes sense, because even though Robotnik can keep coming back in the games, Jim Carrey demands a high price tag and may be done with the sequels.Join our mailing listGet the best of Den of Geek delivered right to your inbox!Then again, Carrey is one of the best parts of the movies and a big draw for those indifferent to the adventures of fast furry animals. Sonic CD, the game that introduced Metal Sonic and Amy, has a time-travel conceit, sending the heroes through various periods in pursuit of Eggman.Could this mean that Robotnik lives in the future and sent Metal Sonic back to the past to destroy his hated enemy? And could Amys adoration of Sonic come from the fact that she grew up with his legend, instead of the usual little-girl crush from the games?Well find out when Sonic the Hedgehog 4 inevitably gets announced.Sonic the Hedgehog 3 is now playing in theaters nationwide.