Metroid (series)

The Metroid (メトロイド Metoroido) games are a series of video games produced by Nintendo. One of the company's most successful franchises, the series spans through several Nintendo systems, with the first game, Metroid, released in 1986.

The Metroid games chronicle the missions of bounty hunter Samus Aran in a science fiction setting which has some similarites to the Alien movies. Central plot elements are the Metroid organisms and the Space Pirates which try to exploit the Metroids' powers. The gameplay combines adventure based on exploration and item-gathering with platformer and shooter dynamics. The Metroid games are famous for their nonlinear gameplay, where you can complete a game with a fraction of the items available in the game.

As of July 2007, 10 games in the series have been released. This includes four main games (Metroid, Metroid II: Return of Samus, Super Metroid, and Metroid Fusion), a Classic NES Series port and remake of Metroid (Metroid: Zero Mission), a spin-off Nintendo DS game (Metroid Prime Pinball), a first-person adventure game, with wireless and online multiplayer (Metroid Prime: Hunters), and a nearly complete trilogy (Metroid Prime and Metroid Prime 2 having been released) with the third game in the trilogy Metroid Prime 3: Corruption underway for the Wii.

Overview
The Metroid games are set in the same universe. They share most main characters and gameplay elements, with a few notable exceptions.

Samus Aran, the main character and heroine, is a bounty hunter, though in Metroid was known as a "space hunter". She wears an extremely powerful and adaptable exoskeleton made by the ancient Chozo adapted to fit her.

The Metroid species are large, jellyfish-like creatures with a visible nuclei. They are capable of absorbing the life energy from any living organism; generally causing the death of the victim in the process. Metroid II established a five-stage life cycle in which the Metroids native to SR388 go through two stages of ecdysis followed by two stages of mutation, thus maturing through four forms: Alpha, Gamma, Zeta, and Omega. Metroid Prime introduced two new, Phazon-mutated forms: Hunter Metroids, which sport tentacles enabling long-range energy siphoning; and Fission Metroids, which divide into two new Fission Metroids after absorbing a certain amount of energy. Metroid Prime 2: Echoes has a Phazon-mutated subspecies of Metroids, known as the Tallon Metroid. Instead of abosrbing all of their power from victims, they can feed directly off Phazon. They are born as Infant Metroids from cocoons and mature into adulthood when exposed to Phazon. Echoes also introduces Dark Tallon Metroids; Tallon Metroids corrupted by the Ing.

The main villains of many of the Metroid games are the Space Pirates. Mother Brain is the biomechanical defense of the planet Zebes. Kraid appears as an important boss in Metroid, Metroid: Zero Mission, and Super Metroid. Ridley, a leader of the Space Pirates, appears in Metroid, Super Metroid, Metroid Fusion, Metroid: Zero Mission, and in Metroid Prime, and in the latest installment, Metroid Prime 3: Corruption. The organization also includes a winged, mantis-like species, the KiHunters. The Space Pirates are very interested in Metroid research, especially in using Metroids for energy generation or as soldiers. Their Phazon experiments produced all the Metroid variants seen in the Prime games.

Gameplay
The gameplay of all Metroid games revolves around Samus collecting items or power-ups that give her the ability to overcome obstacles. Many of the items recur throughout the series, with some modifications, such as the Morph Ball, which allows her to curl into a small ball to access tight spaces and drop bombs. Despite the series having a chronological element to it, each game requires the acquisition of the upgrades. For instance, Metroid Prime occurs just after the first Metroid, though Samus starts with the same minimal gear.

The main enemies of the games in the Metroid series are divided into two groups: bosses and final bosses. Each game contains multiple bosses that are often encountered by entering a large sealed room and engaging in combat with a large creature. When successful, the room opens and allows further progress, usually resulting in obtaining an item. Final bosses are at the end of each Metroid game, and usually consist of a fight similar to a normal boss, and then a timed dash back to Samus's gunship to complete the game. In Metroid Prime, however, unlike many Metroid games, Samus only dashes back to her gunship at the beginning of the game, her power-ups malfunctioning along the way.

In Metroid and Super Metroid, Kraid and Ridley make appearances as bosses, with Mother Brain as a final boss. In some of the games, a Metroid in some form can take the role of a boss, and sometimes even a final boss. The combat model for bosses and final bosses is usually the same, though there are a some exceptions throughout the series.

The Metroid Prime titles diverge from the typical gameplay of the series by presenting the game through Samus's first-person perspective. As a result, the Prime titles contain heavy first-person shooter elements while retaining the sense of exploration and item collection from the 2D series. An additional element present in the Prime series is the ability to scan creatures and objects to obtain information about them.

Evolution of story telling
The narration of the Metroid series has changed substantially throughout the various installments. While the original Metroid has a story in the instruction booklet, this was notably changed in Super Metroid, with the opening narrated by Samus herself. With the releases of Metroid Prime and Metroid Fusion, the series took on a more detailed plot. While both games expanded the use of in-game cutscenes, dialogue, and narration, Prime makes use of the Scan Visor to give Samus the option of uncovering information about the plot, thus allowing the player to immerse themselves at their own pace. Metroid Prime 3: Corruption features voice acting, the first in the series to do so.

Third/Fourth generation
The original Metroid was released for the Famicom Disk System (FDS) in 1986 and the Nintendo Entertainment System (NES) in 1987, introducing Samus Aran, who at the time was unusual in being a female video game character. In the Japanese version of the manual, Samus was referred to in a gender-neutral way of speech as to not spoil the surprise for the players completing the game and thus seeing Samus as a woman, though the North American version mistakenly used male descriptions for her. Featuring a huge world where you choose which direction to explore, Metroid was notable for providing one of the first highly non-linear game experiences on a home console. Because of the time required to play through it, a password save system on the NES and a saved-game slot system on the FDS were implemented to let players take breaks and resume later, being among the first games with these features. Subsequent Metroid games removed the password function, relying entirely on battery-backed or memory-card saves. Metroid has remained one of the most popular games from the NES era. The first sequel, Metroid II: Return of Samus, was released in 1991 for the Game Boy. Unlike Metroid, the goal is not primarily to collect items but to locate and kill Metroids on a new planet, SR388. Metroid II contributed to the series' development by providing a set of new weapons and items, and also revealed some details about the Chozo and Metroids. Although it received positive reviews, it is the least popular in the Metroid series; possibly due to its greyscale graphics and fairly linear gameplay. The third game in the series, Super Metroid, was released for the SNES in 1994. It returned to a gameplay style closer to that of the first game, with many more power-ups available to Samus. Super Metroid is set on the same planet as the original game, but with help from the capabilities of the SNES, features larger and more diverse environments, as well as a more detailed plot than was found in the first two games. Super Metroid was one of the most popular games for the SNES when it debuted, receiving praise for its graphics, sound, and size. It has remained popular, frequently occupying top positions in "greatest game of all time" lists, including a number one spot awarded by Electronic Gaming Monthly.

Sixth/Seventh generation
In 2000, six years since the last Metroid game, Nintendo announced that Retro Studios was developing a new Metroid game for the GameCube, and that Nintendo itself was creating Metroid IV for the Game Boy Advance. Both games were released in 2002 with Retro Studios' game title Metroid Prime and Metroid IV renamed Metroid Fusion. Fusion took place some years after Super Metroid ended, whereas Prime is takes place between the series' first two installments. Released nearly simultaneously, the games also feature connectivity bonuses: players who beat Metroid Prime can play through the game with Samus wearing the new Fusion Suit; beating Fusion allows unlocking the original Metroid as a playable game. Although much-hyped, Prime was controversial before its release. All of the previous Metroid games were 2D, whereas Prime was to be 3D and have a first-person shooter perspective. Players also wondered about how good the game was going to be as Prime was created by a second-party developer instead of an internal Nintendo team. Some players believed the game would simply be a Halo rip off, though Nintendo countered this by referring to Metroid Prime exclusively as a "first-person adventure". When released, critical reception was incredible. Reviewers and fans found Metroid Prime to have preserved and developed the Metroid theme and gameplay, and it is among the most highly rated games of all time among game critics. Metroid Fusion, although well recieved as well, was criticized for its linear gameplay.

A second Metroid game for the Game Boy Advance, Metroid: Zero Mission, was developed by Nintendo and released in 2004. It is an remake and re-telling of the original Metroid story, featuring areas and gameplay elements from Metroid as well as entirely new ones. The story, which sheds a little more light on Samus Aran, is much more detailed than in Metroid. Zero Mission also included an emulated version of the original Metroid as an unlockable bonus.

The third and fourth Metroid games for the Game Boy Advance were direct ports of both the original FDS Metroid and the North American NES port. The FDS version was released as Famicom Mini: Metroid in Japan, and the NES version as Classic NES Series: Metroid in North America and NES Classics: Metroid elsewhere.

A second GameCube Metroid game was released in 2004 titled Metroid Prime 2: Echoes. Echoes is a direct sequel to Metroid Prime and was developed by Retro Studios. It is a first-person adventure in the style of the first Prime, but introduced a new device: the concept of the light and dark worlds, somewhat similar to that seen in The Legend of Zelda: A Link to the Past. It also introduced a new ammo system, as beams never had ammo before.

In 2006, the Metroid Prime series went portable through the release of Metroid Prime Hunters for the Nintendo DS. It is largely credited as being the finest first person adventures/shooters to be released for any handheld system. Though many new weapons, hunters, worlds, bosses, and mazes were added, the game is said to be more linear than its many other counterparts. However, the multiplayer more than makes up for this minor criticism, offering numerous modes and online play via Nintendo Wi-Fi Connection.

Chronology and storyline
The chronology of the Metroid series does not match the release order of the games. According to the official timeline released by Nintendo, the games currently released are ordered as follows:
 * Metroid and Metroid: Zero Mission (1986/2004): Samus travels through the caverns of the planet Zebes to stop the Space Pirates from exploiting the Metroid species for galactic domination. She confronts the cybernetic lifeform Mother Brain, as well as its guardians, Kraid and Ridley. In Metroid: Zero Mission, it is revealed that afterwards Samus was ambushed by Space Pirates after defeating Mother Brain and escaped from Zebes, and her ship crash-lands back on the surface. Stripped of her Power Suit and her gunship destroyed, she is forced to infiltrate the Space Pirate Mothership in order to find a way off the planet with only an emergency pistol for protection. After receiving a fully-powered suit from deep within the Chozo ruins, she steals an escape pod from the Space Pirate Mothership, as well as triggering its self-destruct sequence after eliminiating Mecha-Ridley.
 * Metroid Prime (2002): Samus receives a distress signal in her new ship and travels to Tallon IV to stop the Space Pirates from exploiting a powerful radioactive substance known as Phazon. She discovers that the ancient people who raised her and bestowed her with the Power Suit, the Chozo, once settled on Tallon IV, and their disappearance, as well as the emergence of Phazon, is due to a meteor crashing on the planet at an unknown date. The Chozo sealed away the source of the Phazon, and left the planet. Their prophecies foretold Samus' arrival, and they left her numerous weapons to help her defeat the source of the Phazon. After gathering all the abilities, having her suit corrupted by Phazon and collecting the 12 artifact keys, she unseals the Impact Crater and confronts Metroid Prime, a mutated Metroid and the source of the Phazon. After killing it, Metroid Prime absorbs Samus's Phazon Suit, and dies. However, collecting 100% of the items reveals that Metroid Prime has lived on, wearing the Phazon Suit.
 * Metroid Prime Hunters (2006): When the Galactic Federation receives an unusual telepathic message, Samus is sent to the remote Alimbic Cluster in the Tetra Galaxy to uncover the rumored "Ultimate Power." Six rival bounty hunters that also heard the message attempt to secure the power before anyone else, including Samus. It transpires that the promise of ultimate power was actually a lie sent by the creature Gorea, sealed away by the Alimbics in a void between dimensions. After killing Gorea, Samus and the six bounty hunters all leave the cluster, empty handed, but alive.
 * Metroid Prime 2: Echoes (2004): Samus is sent to investigate the planet Aether after communication with a squad of Galactic Federation troopers was lost. Samus finds them all dead, killed by several creatures, mainly consisting of an evil race called the Ing. Upon meeting the only remaining member of Luminoth race, Samus learns Aether has been split into two dimensions by a meteor similar to the one that crashed on Tallon IV. Samus helps save Aether from the Ing, but encounters Metroid Prime in the process, who's genetic code has mutated and is wearing a Phazon version of her Varia Suit.
 * Metroid Prime 3: Corruption (2007): The third and final chapter of the Metroid Prime trilogy. Mark Pacini, the game director at Retro Studios, states that "Metroid Prime 3: Corruption is a direct sequel to Metroid Prime 2, and the goal of the game is to wrap up the storyline that involves the material Phazon." What is known so far is Metroid PRime and the Space Pirates have joined together in an attempt to corrupt the universe with Phazon. Samus tries to stop them, but she becomes corrupted by the Phazon.
 * Metroid II: Return of Samus (1991): Following the events of the previous chapters, the Galactic Federation deems the Metroid species too dangerous to exist, and, after their own failed attempts, employ Samus to travel to the Metroid homeworld, SR388, and exterminate the entire species. After killing every Metroid, Samus finds an unhatched egg sac. As she prepares to destroy it, a Metroid larva pops out and believes Samus is its mother. It follows her back to her ship, and Samus hands it over to the Galactic Federation for research.
 * Super Metroid (1994): Samus receives a distress signal from the research lab where she took the Metroid hatchling at the end of the previous game. She returns just in time to see Ridley stealing the hatchling. She then follows Ridley to the rebuilt base on Zebes to stop the Space Pirates in their new plan to clone the Metroids and use them as a weapon. She kills the reborn versions of Ridley, Kraid, and Mother Brain, blowing up Zebes and killing the last remaining Metroids.
 * Metroid Fusion (2002): While acting as a bodyguard for researchers on the planet SR388, Samus is infected by a creature known as the X Parasite, the original prey of the Metroids. Doctors surgically remove Samus's Power Suit and cure the X infection with a vaccine created from Metroid DNA, allowing her to survive the parasite. She is then sent to investigate a disturbance at the space research facility, Biologic Space Labs, where researchers attempted to contain the infected Power Suit. It turns out that the infected suit became an X mimicking Samus, the SA-X. This released other X parasites inside the other specimins, and began to infect the entire station. Samus attempts to stop them, but eventually decides, with the help of her computer Adam, to crash the station into SR388, killing both the X on the station, and on the planet.

Metroid Prime Pinball is not a separate canon game in the Metroid storyline but actually retells the story of the original Metroid Prime in pinball format. It includes several of the same bosses and areas, such as Phendrana Drifts, Thardus, and Metroid Prime. Despite playing as a pinball game, there are a number of powerups that can be collected in the multi-game mode, including missiles and power bombs.

Speedrunning
The Metroid games have been a popular target for speedrunning, completing a game in the fastest time possible. In addition to the nonlinear level design that allows alternate routes to be taken through the games, the Metroid games encourage speedrunning by displaying item collection and completion time statistics at the end of the game. Speedrunning is also encouraged by the fact that completion time is one of the primary factors determining what ending the player sees, and completing the game in a short time allows the player to see Samus without her suit on.

To finish a game as quickly as possible, speedrunners exploit glitches and secrets that provide shortcuts which are in many of the games. For example, the key to speedrunning in Super Metroid is the wall jump move, which is not described in the instruction manual but revealed in a secret room in the game. Wall jumping, as well as the shinespark move, also appears in Super Metroid, Metroid Fusion, and Metroid: Zero Mission.

Shinespark
The Shinespark is an ability that debuted in Super Metroid, where it was known as the Super Jump. It has more recently been used in two other Metroid games as well: Metroid Fusion and Metroid: Zero Mission. The name "Shinespark" was officially given to the technique in Metroid Fusion during a "secret" conversation that, to witness, requires the player to perform a complicated series of Shinesparks, or exploit a glitch in the US and European versions. The technique requires the Speed Booster upgrade and allows Samus to break through Speed Booster Blocks as well as some blocks that can be destroyed with Morph Ball Bombs and the Power Beam. Metroid: Zero Mission takes the move one step further by allowing the player to do the move while in Morph Ball form as well.

Suitless Samus
A traditional aspect present in each Metroid title, with the exception of Metroid Prime Pinball, is the ability to see Samus's appearance without her Power Suit. In Metroid, this could be achieved by completing the game under an hour or by entering passwords into the NES version's password screen. Originally used as a method of keeping Samus's gender a surprise, it has become a custom to display an image or movie of Samus without her suit if the player beats the game within a specific time frame and/or finishes the game with a specific percentage of items collected. Metroid: Zero Mission was the first game to break from tradition by including a sequence during the course of normal gameplay in which you are forced to play as Samus after she has lost her powersuit, known as Zero Suit Samus.