The Metroid series is no stranger to horror. Its titular creature is born as a vampiric jellyfish and only grows more gruesome from there, but in the franchise's two most recent games chronologically, Metroid Fusion and Metroid Dread, there's been a decided shift in focus on the more terrifying side of the franchise.

Metroid Fusion stands out as almost a survival horror Metroid game, with most of your journey seeing Samus being underequipped and vastly overpowered by the new threat of the game, the X Parasite. This floating, writhing orb of viscous jelly infects and copies everything it touches, pushing the series beyond sci-fi scares, the dread of the unknown and the danger of alien species into some light body horror. Every element seems to come together, from the ever nagging fear of pursuit or discovery by not only just the creatures that inhabited the B.S.L, but a nigh-unstoppable copy of Samus that can show up at the worst of times, to some expertly utilized musical stings, Metroid Fusion became the horror movie of the franchise.

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The X Parasite and Horror of the Body

Official screenshot for Metroid Fusion

Metroid Fusion begins with Samus escorting a group of researchers back to the surface of SR388, where the X Parasite infects her Power Suit, which up to this point was believed to be impregnable. The X Parasite had grown so completely into her system that it can't be removed, compromising the suit's functions. To the point of desperation, Samus has Metroid DNA introduced into her system, as the now eradicated foe were the X's only natural predator.

Samus is often the focal point of power in any Metroid game, expanding and growing as areas are explored, but Fusion immediately puts her at a disadvantage. Not only is the X Parasite an unknown, but it casually pierces her defenses and strips away a lifetime of hard-earned power-ups, a mainstay of any Metroid game but one that is used in Fusion to further drive home the new threat of the X. They don't start as just a threat that a handful of super missiles can reduce to ashes, but something more personal, a crucial reminder of vulnerability. The X destroys the Power Suit, taking Samus' most iconic and potent weapon, but the introduction of the Metroid DNA changes her even further, into something both less and more than she used to be.

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SA-X, the Creeping Dread of a Perfect Copy

Official screenshot for Metroid Fusion

Early on in Metroid Fusion, the other half of the threat of X is revealed. Not only do they infect and destroy, but they also replicate, able to accurately recreate organisms of any type, including the walking incarnation of destruction that would be a fully powered Samus Aran with no heroic spirit to root her. The SA-X is born of the infected plates of Samus' Power Suit, bringing with it each weapon and power the bounty hunter has earned.

The introduction of the EMMI seems almost like a direct nod back to the SA-X, which were some of the best sequences of the series. The SA-X is better than Samus in every way for most of Fusion, so there's no choice but to run, all the while a tingling score keeps the tension at an 11. While the EMMI seem to be more localized and at the very least contained to their own areas, if they manage to invoke some of the dread that even the echoing footsteps of the SA-X could, then they'll have lived up to the new title's name. With the potential return of the X in Dread, there is a whole bevy of monstrous terrors that could be waiting along with the EMMI.

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A Host of Nightmares, Consumed and Made Worse

GBA Metroid Fusion Nightmare Battle

The Biologic Space Laboratory that serves as Fusion's setting is also home to various nasty creatures. Living up to its name, the Nightmare is a biomechanical construct that is effectively teased as Samus explores its housing area, a shadow that whips across the background of Sector 5 with no explanation until much later. The inevitable confrontation is dominated by the sheer bulk of the monstrosity and its ability to manipulate gravity. In some phases of the fight, Samus' missiles will fall useless to the floor feet from her, a firm rebuke of her usual answer to more threatening opponents. Even as the creature melts away from damage, you forget it's just a copy, a forced projection of an X.

The Nightmare is only one of these fearsome encounters in Metroid Fusion, each teased nearly as well, ranging from the arachnid Yakuza that eventually sheds its legs so it can become a whirling dervish that rivals Samus' Screw Attack, to Nettori, the source of the encroaching green life that Samus needs to deal with in Sector 2, each mimicries of life wrought by the X as revealed after a damage threshold is breached and their core is exposed, adding tension these fights as resources dwindle and the looming threat of the X-Core sinks in. Even Samus' arch-rival Ridley is inevitably resurrected through the X. If the parasite actually is still active by the time of Metroid Dread, dozens of possible strains of DNA could have been used, maybe even to recreate some returning favorites.

Metroid Dread is shaping up to be a worthy successor when it comes to the tension and horror Metroid Fusion had to offer. Finally getting to see the further ramification of Samus' X and Metroid-infused system in the first narrative sequel to Fusion in 19 years, as well as the potential fate of the X, should keep the tension high until Metroid Dread releases on October 9th on the Nintendo Switch.

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