List of retcons and inconsistencies in Metroid

Retroactive continuity, or retcon for short, is an act of alteration, addition, or subtraction of previously established facts in a work of fiction. When a series is extended, the likelihood of retconning and inconsistencies increase. Metroid is not an exception to this.

Metroid

 * "The Federation researchers had named it 'Metroid' and were bringing it back to Earth." (Metroid instruction manual, p. 5)
 * "It seems that the word Metroid in the Chozo language can roughly be translated as 'ultimate warrior.'" (Metroid Fusion instruction manual, p. 40)
 * While the contradiction is apparent, it should be noted that this inconsistency was resolved in the Metroid 2002 manga. Indeed, "Metroid" is a Chozo word. The Galactic Federation called that particular species, "Metroid," after Samus told the Federation the name of the species.


 * "Warning! Beware of the water! Fall in and Samus' energy is weakened." (Metroid instruction manual, p. 19)


 * This was changed to acid in Metroid: Zero Mission. Before that, Samus showed no weakness by stepping into water in Metroid II: Return of Samus.


 * "With these boots, Samus can jump one-and-a-half times higher than he normally can." (Metroid instruction manual, p. 24)


 * "With these boots, Samus can jump more than twice as high as she normally can." (Metroid II: Return of Samus instruction manual, p. 17)


 * In Metroid, Samus can enter Norfair without the Varia Suit and not take heat damage. In Super Metroid and its successors, Samus must have the Varia Suit in order to enter Norfair and other superheated regions.


 * Originally there were two types of Zoomers in Metroid: Red Zoomers and Yellow Zoomers, which were weaker. While called Red Zoomers, the hue appears purple in the instruction manual as well as in the game. In Super Metroid, Samus only encountered Geemers, which presumably would be Red Zoomers, considering their hue. Technically, the first time Zoomers and Geemers were considered to be a separate species was in Metroid Prime. Metroid: Zero Mission still follows the original concept of Zoomers.


 * "It's the head of the Mini-Boss Hideout II. It jumps up into the air and breathes fire." (Metroid instruction manual, p. 39)


 * "It whips out at enemies with its long tail and spits fire while flying through the air." (Super Metroid instruction manual, p. 31)


 * Canonically, Ridley was never called by a particular gender up until Metroid Prime. However, he was referred to as "Master Ridley" in the Super Metroid comic on page 62, which would imply that Ridley was a male. Male pronouns were also used for the Ridley trophy in Super Smash Bros. Melee.

Metroid II: Return of Samus

 * Originally, the Spider Ball was a "sticky ball" that gave Samus "the power to move across the walls and ceiling unhindered by gravity." (Metroid II: Return of Samus instruction manual, p. 17) However, in the Metroid Prime trilogy, the Spider Ball uses magnetic rails to cling on certain areas.


 * "This extremely powerful weapon fires a beam that can penetrate solid walls." (Metroid II: Return of Samus, p. 22)


 * The Plasma Beam was given the capability of piercing through solid walls in Metroid II. Since Super Metroid, only the Wave Beam has been capable of passing through solid walls.


 * The Omega Metroid, as well as any of the other Metroids in Metroid II are only vulnerable to missiles. The Ice Beam will not work. However, in order to defeat the Omega Metroid in Metroid Fusion, Samus must use the Ice Beam. Missiles will not work.


 * The Gravity Suit, first introduced in Super Metroid, has a consistency of allowing Samus to enter magma or lava. However, for unexplained reasons, in Metroid Prime and Metroid: Other M, Samus is unable to enter these hazardous liquids without taking damage.


 * "These boots allow Samus to run at super high speed and make her invincible as she runs through enemies." (Super Metroid instruction manual, p. 24)


 * While it says that when active, Samus is invincible, in-game proves that Samus is not really invincible. This is also proven false in Metroid Fusion when Samus shinesparks in superheated rooms without the Varia Suit. In Metroid: Other M, Samus can be stopped by a beam from an FG-1000, as well as the electric barriers outside of the corridors that lead to the Geothermal Power Plant.


 * In Super Metroid, Samus first shows the ability to wall-jump by the Etecoons and shinespark by a Dachora. This is confirmed by Samus after she encounters the Etecoons and Dachoras in Fusion. She even says that they taught her abilities she did not even know she had. However, in Metroid Prime 2: Echoes and Metroid Prime 3: Corruption, when Samus acquires the Screw Attack, she is able to wall-jump. These two games occur before Super Metroid. Furthermore, in Metroid: Zero Mission, Samus is able to wall-jump and shinespark.

Metroid Fusion

 * "While it has come to light in recent years that the Metroids were created by the ancient Chozo civilization, it is not common knowledge that they were created for the purpose of driving out the X parasites." (Metroid Fusion instruction manual, p. 40)


 * In the Metroid 2002 manga, we see the first Metroid created in order to reduce the number of X parasites on planet SR388. Fusion supports this. However, the issue arises when the idea of a Phazon meteor strikes Tallon IV, and that a Metroid is feeding on this Phazon fifty years before the events of Metroid Prime 3: Corruption.

Metroid Prime

 * "But the Space Pirates were far from finished. They immediately split their survivors into two main camps. One headed to Zebes to begin rebuilding their ravaged facility and resuscitating Mother Brain, Ridley, and Kraid." (Metroid Prime instruction manual, p. 9)


 * While this would be consistent with the Space Pirates spliting into two camps, and that Mother Brain, Ridley, and Kraid would be resuscitated, we only see Ridley resuscitated in Metroid Prime. There is no sign of Mother Brain, and Kraid was going to originally be in Prime, but due to time constraints, this was not possible. Furthermore, in Metroid Prime 3: Corruption, the Aurora Units look quite similar to Mother Brain, and the idea that AU 242 was going to become the next Mother Brain does not make sense in light of the Prime instruction manual.


 * Another problem is that in Super Metroid, Mother Brain retained the organic feature of a brain, while the AUs looked mechanical. To add further problems, Metroid: Other M reveals Mother Brain again with the organic features, although Mother Brain is bio-mechanical. Nevertheless, the idea of AU 242 would have to be scrapped if it is not to contradict Yoshio Sakamoto's games, as well as the Prime instruction manual.


 * In the NTSC version of Metroid Prime, from the Chozo Lore it seemed that Samus once lived on planet Tallon IV. This was retconned in the PAL version, as well as in Metroid Prime Trilogy, likely due to contradiction that Samus was raised on planet Zebes.


 * According to the Space Pirate Data, the Phazon meteor that struck Tallon IV occurred twenty years ago. In Metroid Prime 3: Corruption, the Phazon meteor struck Tallon IV fifty years ago. This was corrected in the PAL and trilogy version, using the word "indeterminable."


 * In the NTSC version of Prime, the Space Pirates found Metroid Prime and contained it to study it, even though the Cipher can only be opened by the twelve artifacts. In the PAL version, Metroid Prime was not discovered or contained, but the Space Pirates were aware that a Phazon-consuming creature dwelled in the Cradle.

Metroid Prime 2: Echoes

 * "The Dark Beam can open purple hatches." (Metroid Prime 2: Echoes instruction manual, p. 17)


 * The black hatch in Echoes is presumed to be such because there are already purple hatches that require the Seeker Missile to be opened, and because mixing black and white makes gray. This is likely an error from Retro Studios.