X Parasite

From Metroid Wiki
(Redirected from X Parasites)
Jump to navigationJump to search
X Parasite
X manga.jpg

The X appearing in the Metroid manga


Metroid: Samus Returns (cutscene)
Metroid Fusion
Metroid Dread

Off-Game Appearance(s)

Metroid (manga)

Damages by
  • Contact
  • Mimicked attacks
Threat Capacity


Natural Habitat(s)


Located in

B.S.L research station

X parasites, or simply X,[2] are the species of parasitic organisms fought by Samus in the B.S.L research station in Metroid Fusion, though their natural habitat is SR388. They invade a host body and absorb the DNA and memories of the host before attaching itself to the creature's nervous system and killing it, enabling the parasite to mimic its appearance. The only known creatures able to combat the X are the artificial Metroids and Samus Aran.

Properties[edit | edit source]

The simplicity in appearance and shape of the X is extremely misleading. Aside from being extremely fatal and quick to multiply, these creatures exhibit signs of an impressive intelligence and even the ability to communicate.

A Hornoad and a Hornoad-X, the difference between a normal and X-mimicked creature

The X attack creatures by first entering the organisms' systems. They then reproduce rapidly, bursting through the creature and killing it, as almost happened to Samus. They proceed to absorb the host creatures' DNA, using it to mimic the host.[3] Upon mimicking a creature, the X also gains the hosts memories, as well as their abilities, though they also gain the creatures' weaknesses, provided they have any.

X also appear to be invulnerable to any kind of weapon. X can only be damaged in their mimicked forms, but cannot be destroyed by any conventional means in their gelatinous forms. Though the weaker ones may be drawn in by it, even the Power Bomb cannot damage them. Beam weapons may at best stun some forms of the X. Larger, Core-X can be stunned by the Missiles, but ultimately only Metroid cells can destroy X parasites.

An X-structure securing an Atmospheric Stabilizer, allowing perfect X-breeding conditions

Aside from the overwhelming capability to mirror any species, the X also show intelligence, using certain creatures to commit to special assignments, such as using the SA-X to attempt to dispose of Samus or using the Human Core-X to destroy the entire B.S.L research station. The X also used the special ventilation system in SRX to adjust the conditions for X breeding. The X were also able to seek out their natural enemy, the Metroids, in the Restricted Laboratory and launched an attack immediately after Samus opened the area for exploration.

Curiously, the X appear to be able to communicate with one another across large distances. This is shown by the Blue X; though they originally attacked Samus while she was vulnerable to them, once she absorbs a couple using the Varia Suit, the remaining X will flee from Samus on sight. Adam hypothesized that the X may have used the memories of a human through Human Core-X to destroy the research station for the mere purpose of defeating Samus, perhaps for the safety of X elsewhere in the universe.[4]

History[edit | edit source]

X on SR388[edit | edit source]

An SA-X being destroyed by Metroids, showing the X vulnerability to the energy-based life forms

The Metroid manga reveals that the Chozo first discovered and named the X on SR388. A camera placed by the Chozo revealed the Xs' destructive nature as one mimicked a Hornoad. In order to combat the X, the Chozo experimented on creating a biological weapon. These weapons would become the Metroids. The Chozo eventually released the destructive Metroids into SR388's environment, where they became the X's predators. Though they succeeded in creating a check to the X's growth, they also created a very malleable species, ready to be exploited by the Space Pirates and the Galactic Federation alike.

The X were hunted to near-extinction by the Metroids. With the extermination of the Metroids on SR388 by Samus, the X began to thrive again, infecting, killing, and mimicking the various life forms of SR388. Although there is no mention of the X in Super Metroid, the were probably in the process of overrunning the planet SR388.[5]

The X within Samus[edit | edit source]

Samus encountering the X Parasite for the first time

While serving as a bodyguard for researchers of B.S.L. on planet SR388, Samus is infected by an X mimicking a Hornoad. Unknown by Samus, the X multiplied rapidly in her nervous system, and during her return to B.S.L, Samus lost consciousness. Just before her Gunship crashes into an asteroid belt, the security system automatically ejects Samus in an escape pod, which is recovered by a B.S.L. Research Station vessel.

The X inside of Samus

Samus is taken back to Galactic Federation HQ to be treated. Because large portions of her Power Suit are infested by X, and because these portions are integrated with her nervous system, they have to be surgically removed. The X remain in Samus's central nervous system, and an experimental anti-X vaccine, Vaccine "Metroid", made from a cell culture from the Metroid Hatchling is used to cure her. As a result, all of the X in Samus are destroyed, and Samus becomes immune to future X infection and gains the ability to absorb other X-Parasites, using their energy to replenish her health and weapons. However, she also inherits the Metroids' weakness to cold as an unexpected side effect of the vaccine.

Samus getting attacked by an X Parasite

X on the B.S.L research station[edit | edit source]

X-infected life forms from SR388 and the infected portions of Samus's Power Suit are transported to B.S.L for research, where the X run rampant through the station's six sectors, partly due to Samus's lifts on the security locks after she arrives to investigate a sudden explosion. The infected parts of Samus's suit became SA-X, a mimicked form of Samus. With this creature and the various other powerful specimens in the Xs' arsenal, the X managed to cause severe damage throughout the research station.

X on ZDR[edit | edit source]

This section of the page is incomplete or missing.
You can help Metroid Wiki by expanding it.

Varieties[edit | edit source]

Yellow X[edit | edit source]

A Green X released from an Atmospheric Stabilizer

Yellow X are by far the most common form of X. They heal a measly ten units of energy. These X can be released by any mimicked species in nearly any condition. It was a Yellow X that initially infected Samus on SR388.

Green X[edit | edit source]

Green X are the second most common X variety. They replenish two of Samus's Missiles. These X can commonly be produced from Core-X by shooting at them with beam weapons rather than missiles.

A model of the Blue X

Blue X[edit | edit source]

The larger Blue X are exceptionally different from the other regular forms of the X. Blue X live only in the cold environments Sector 5 (ARC) and Sector 6 (NOC), and many lay hidden underneath boxes. These creatures appear to exhibit higher thinking capabilities than the smaller X. This can be shown by the fact that they attack Samus when they are able to, and flee when unable, unlike the other X. Out of the four colored X, the Blue X is the only one that can be stunned by shooting at it with a beam or detonating a Power Bomb, the Power Bomb will not draw Blue X to the center of the blast.

Because of their cold nature, Samus is unable to absorb the Blue X until she obtains the Varia Suit, meaning the Blue X will damage her until she defeats the Mega Core-X. After she obtains the suit, Samus will be replenished thirty energy units.

Red X[edit | edit source]

Red X are the most rare X as well as the most useful. Red X are found prior to every boss battle, hiding within the Gadora that guard important doors. These X also appear to morph creatures in a way different from other X. Aside from completely changing the coloration of some creatures, a Red X-mimicked creature is granted immense persistence and resilience. Red X can yield golden Scisers, blue Zero, or even golden Zebesians. In many areas, a locked door will open only when a golden creature is defeated. Red X may sometimes appear out of enemies that appear to be regular, mimicked creature, though this usually only happens when Samus is low on energy and ammunition.

These X recover an astonishing four Energy Tanks, ten Power Bombs, and fifty Missiles.

Core-X[edit | edit source]

Main article: Core-X

Core X are larger, more powerful versions of any previous X. In fact, the Core-X may be a collection of previous X, as shooting Core-X with beams will cause it to release some Yellow or Green X. These powerful X are those that have absorbed a powerful ability along with a powerful creature. They appear after Samus has dealt a significant amount of damage to a boss, such as Nightmare or Arachnus. Unlike other X, these X are protected by a spiky shell, and will ram Samus as a last ditch effort to repel her. If Samus breaks through the shell using her Missiles, she will be able to absorb the Core-X, gaining the ability it has stolen and large amounts of energy and ammo depending on how powerful the Core-X was.

There also exist a series of Core-X with a more durable shell and the ability to fire beams known as Hard Core-X. These X are Core-X that have absorbed one of Samus's beam abilities. They have an "eye" which they use to shoot their beam with. Their shells cannot be destroyed by Samus's Missiles, she must instead fire into the eye to destroy it.

Data[edit | edit source]

Manual[edit | edit source]

Sprite[edit | edit source]

Game Yellow
Metroid Fusion Yellow X mf Sprite.png Green X mf Sprite.png Red X mf Sprite.png Blue X mf Sprite.png

Gallery[edit | edit source]


  1. "That creature took on the host's memories, appearance, abilities, everything. It sucks everything dry. Utterly terrifying. Can you not see that if a mimic such as this were to infiltrate a population it could replicate almost anything indefinitely! With evil taking the form of an ally, the galaxy could be overthrown. It is truly the worst kind of creature... it has no name but... We call it X." —Metroid (manga), Old Bird, Vol Metroid Fusion Ch {{{4}}} Pg(s) {{{5}}}
  2. "It was only later that I learned the identity of my attacker: the parasitic organism we now know as X. Unaware of my condition, I was returning to the station when disaster struck." —Samus Aran (Metroid Fusion)
  3. "The gelatinous X parasites invade and rapidly reproduce, killing the host creature. They also absorb DNA and use it to mimic the host. You were almost killed by an X infection. Only the Metroid vaccine saved your life. It seems Metroids were the main predators of the X. That's why the vaccine worked so quickly and so well." —Adam Malkovich (Metroid Fusion)
  4. "The X mimicked a crew member... It all makes sense now. The X can absorb the memories and knowledge of their prey. What an astounding find. HQ was very impressed. But don't you find it strange? This could have destroyed the station with the X in it, not to mention to SA-X. Unusual for a self-preserving species like the X. Unless... Your presence is an even greater threat, a threat to the existence of X elsewhere... This is only a hypothesis... Perhaps... Their survival instinct is in conflict with their newly-borrowed intelligence... Don't let your guard down yet. The X are still a threat. Samus, I see bio-signs on the Habitation Deck. Survivors? The infected crewman you saw had survived until recently. Maybe there's a chance... The signs emanate from here." —Adam Malkovich (Metroid Fusion)
  5. 5.0 5.1 "X seem to have originated on SR388, which is also home to their sole predator, the Metroids. Since Samus Aran exterminated the Metroids on SR388, the X have overrun and infected most of the life-forms on the planet." Metroid Fusion Instruction Booklet, Pg 11
  6. "X infect other creatures and grow in the nervous systems of these host organisms. Even more worrisome is their ability to control and assume the appearance and behavior of other life-forms through mimesis, a process of infection and replication. The X mus somehow be capable of assuming the memories and genetic information of their hosts." Metroid Fusion Instruction Booklet, Pg 11
  7. "The X parasites react adversely to the presence of Metroid tissue and even associate the Metroid cells in Samus's body with their natural enemies. X parasites within reach of Samus will attack viciously and relentlessly." Metroid Fusion Instruction Booklet, Pg 11
  8. "Since receiving the Metroid vaccine, Samus has begun to incorporate some properties of Metroids into her own genetic makeup. This allows her to absorb X parasites in their gelatinous form to replenish her supply of energy and missiles. After defeating organisms infected by the X parasites, Samus must capture the X in its true form as it escapes from the dead host." Metroid Fusion Instruction Booklet, Pg 11

Pathogens and Conditions