Sonic the Hedgehog 2 may be the most hotly anticipated film coming to theaters this year, and fans have been hyped since the first announcements. The second film based on the almost stunningly popular video game franchise has fans everywhere wondering exactly what parts of their favorite games they'll get to see on-screen.

Ask any fan of video games who Sonic the Hedgehog's nemesis is, they'll have plenty to say about Dr. Robotnik, but his rogues' gallery is shockingly extensive. The game franchise has introduced countless bosses, but there's one reoccurring threat that might be the big reveal of Sonic the Hedgehog 2, or even a nod to the next film in the series.

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Fans of the first Sonic the Hedgehog film will remember that the film concluded with Dr. Robotnik banished to the uneventful Mushroom Planet. They may also remember that the mad scientist kept a single quill from Sonic's spiky pelt, giving him access to studying the hedgehog's strange powers. The trailers for the upcoming sequel reveal that Eggman also managed to get ahold of the Master Emerald, an artifact of immense power from another world. Through some combination of the two, he is able to create a host of new killer robots. Though it has only appeared for a few short moments, the film shows off a giant robot with the style of an early game boss. Also entering the fray is Knuckles, who the ads seem to be shaping up as a new rival for Sonic. That classic red echidna is immediately a fan favorite, but he's rarely been depicted as an antagonist when it comes to Sonic stories. Between the giant robot and Knuckles, the film may be keeping its real biggest threat under wraps.

Metal Sonic - Sonic The Hedgehog Zodiac

Metal Sonic was introduced in 1993's Sonic CD, but the concept of Robotnik crafting a robotic facsimile of the blue blur dates back to Sonic 2 the year prior. Metal Sonic is one of those characters in genre fiction that starts out extremely powerful and just gets stronger at every turn. Probably the greatest invention of Dr. Eggman, Metal Sonic is consistently brought up as a secondary antagonist throughout the Sonic franchise. In a couple of appearances, Metal Sonic overpowered or outwit his own creator, occasionally even forcing Eggman and Sonic onto the same side. He even takes on a giant monster form from time to time, rendering him one of the scariest designs in the franchise. As a cold and calculating machine, his only drive is to defeat and destroy Sonic. Given the state of the characters after the first film and the source material throughout, it's likely that Metal Sonic is on the horizon.

Dr. Robotnik's time away and access to one of Sonic's quills could give him the technology he needs to create a robotic hedgehog with the blue blur's power. The massive robot looks like a climactic final setpiece, but if the trailer dialogue is to be believed, it appears in the same scene that Sonic meets Tails. The duo has a ton of adventures after that moment, so perhaps that battle takes place somewhere in the second act, rather than the conclusion. Much of the basic outline of the film closely resembles the game Sonic 3 & Knuckles, and Sonic robots were already common by that point. It could seem like packing Metal Sonic into a film that's already introducing so much could be overdoing it, but there's actually a perfect place for the machine in the narrative.

Last year's Godzilla vs. Kong was a film about two characters, both of whom audiences know as heroic figures, battling to the death over a personal conflict. Fans knew from the start that neither Kong nor Godzilla would likely slay the other, and they were proven right with the film's big third-act twist. The film introduced Mechagodzilla, a robotic duplicate of the protagonist designed by an old nemesis to defeat him. The machine was so powerful that the warring pair was forced to put aside their differences to face a new threat. Anyone who knows anything about Sonic knows that Knuckles is a friend and ally throughout the series, and Metal Sonic would be the perfect threat to force the two onto the same side.

While this would be a fairly simple narrative leap, it's also entirely possible that Metal Sonic could be set up for a later film. Sonic and his new friends Knuckles and Tails banding together to defeat the unstoppable machine is a solid direction for the end of a trilogy. Maybe even Eggman will be forced to join the side of good, as he has a few times before. There's no guarantee that the iconic enemy will make an appearance in the Sonic film franchise, but with the source material and narrative details falling into place, it seems very plausible. As Sonic the Hedgehog 2 comes ever closer, it just seems to look better with every new detail.

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