Though Nintendo's Metroid franchise has never been its most successful in terms of sales, the games' iconography has become some of the developer's most recognizable. Both The Legend of Zelda and Metroid franchises are celebrating their 35th anniversaries this year, and Nintendo announced Metroid Dread at E3 2021 to help celebrate the latter as Retro Studios' Metroid Prime 4 continues production.

Dread is considered "Metroid 5," the next entry in the series' linear timeline of 2D platformers following 2002's Metroid Fusion. It's being created by MecurySteam, the studio that worked on the 2017 3DS remake of Metroid 2 called Metroid: Samus Returns. However, anyone jumping directly from Samus Returns to Dread will likely find the titular alien menace playing a far more subdued role in this upcoming Switch game. Samus Aran may be the series' protagonist, but it being titled Metroid is fitting given how much the overarching narrative revolves around the Metroid species' role in galactic affairs.

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The Origin of the Metroid

species history nintendo

The Metroid species is not a naturally occurring part of any ecosystem in the Metroid universe; they were originally created by an ancient, technologically advanced race called the Chozo. These bird-like forerunners hoped to use the creation to kill off the dangerous X Parasites found on SR388, which can kill and assimilate any life form to gain whatever abilities they possess - including some degrees of sapience, as seen in Metroid Fusion. However, the Metroid were largely uncontrollable and began evolving, which contributes to the demise of the Chozo people.

A good many years later, Metroid are obtained by the Space Pirates and brought to their base of operations on Zebes. Their leader Mother Brain, who is also revealed to be a corrupted AI built by the Chozo in Metroid's prequel manga, has designs to use the species as a bioweapon due to the way it feeds off of other creatures' energy. This is when Samus enters the picture, as the original Metroid on NES depicts her journey to stop Mother Brain.

Chronologically, the Metroid Prime trilogy takes place after Metroid (NES). These games follow Samus across the galaxy as she attempts to stop the Space Pirates' various ongoing operations. A number of unnatural Metroid species mutated by Phazon are found in the Prime games, namely on Metroid Prime's planet Tallon 4, and Dark Samus is a reincarnation of the titular Metroid Prime.

The Last Metroid Is In Captivity

10 Super Nintendo Games Everyone Should Play - Super Metroid title screen

Metroid 2, and its remake Samus Returns, chronicles a Galactic Federation mission that sends Samus to SR388 after a research team goes missing. There she's tasked with exterminating the Metroid threat, and essentially spends the rest of the game committing genocide. Here it is discovered that the iconic green, jellyfish looking creatures that many know a Metroid to be is only its larval state. As Samus delves into the depths of SR388, she encounters various stages in its lifecycle: Alpha, Gamma, Zeta, and Omega. At the end of the game she finds the Metroid Queen, and destroys her too.

After finishing off the Metroid Queen, Samus comes across one last egg and the baby Metroid that hatches from it imprints upon the bounty hunter. Samus takes the baby to the Ceres Space Colony where it can be studied. This leads to probably the most iconic line in the franchise, "The last Metroid is in captivity. The galaxy is at peace." That peace does not last long however, as soon Ceres is attacked by the Space Pirate Ridley whom Samus has battled a number of times (including in a cybernetically enhanced form throughout the Prime series and in Samus Returns).

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Thus begins the SNES classic Super Metroid, where Samus returns to Zebes in order to find the baby Metroid, defeat Ridley, and ultimately stop a reconstructed form of Mother Brain. Toward the end of the game Samus discovers the baby Metroid has grown enormous, but it still recognizes the bounty hunter and lets her live. In fact, it goes on to help her defeat Mother Brain by absorbing its energy and transferring that to Samus.

The baby Metroid is killed by Mother Brain as it assists Samus, and part of the plot in Metroid: Other M deals with her feelings of loss. Though the game is controversial to say the least, particularly in the way it handles Samus' characterization, it bridges the gap into Metroid Fusion.

Metroid Fusion and Beyond

Samus Aran from Metroid Fusion

The events of Metroid Fusion begin with Samus on SR388 alongside a new Galactic Federation research team, as they discover and are subsequently attacked by an X Parasite - now free to propagate due to the loss of its main predator. The infection threatens to kill Samus, but the Federation saves her life with a vaccine developed using cells from the baby Metroid. Although Samus lives, her DNA is inextricably linked with Metroid DNA, meaning she also inherits the species' intolerance of cold temperatures.

Despite the Federation developing a vaccine for Samus, the X Parasite takes over the research station orbiting SR388, leading the bounty hunter to take on monstrous versions of previous species she's battled that have been assimilated. The biggest threat is SA-X, an X Parasite that used Samus' power suit to create its nigh-unstoppable form. Eventually she discovers a secret Metroid cloning facility on the station, and the Metroid clones are set free by SA-X in an attempt to destroy them. With the station overrun by X Parasites and Metroid, Samus sends it into a collision course with SR388, destroying both.

As of this writing it's unclear whether the Metroid will play any role in Metroid Dread. The game has been in various stages of development for over a decade, and the story surrounding its titular alien menace seems to have ended. However, developer Yoshio Sakamoto confirmed Dread is the end of the story arc stemming from Metroid (NES), and one connection appears likely. On the official Nintendo website listing for Metroid Dread, the E.M.M.I. robots found on planet ZDR are described as former "DNA-extracting research machines," which could play into Samus' lingering baby Metroid DNA from the vaccine she received in Fusion. However, fans will just have to wait and see what happens when the game releases later this year.

Metroid Dread launches October 8, exclusively for the Nintendo Switch.

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