History Characters / MetroidXParasites

An X duplicate formed from the cryogenically preserved corpse of Ridley's clone. For the original's tropes, see [[Characters/MetroidRidley here]].

An X which possesses a weakened Raven Beak and combines his biomass with Kraid, creating a monstrous hulking fusion. For the original's tropes, see [[Characters/MetroidRavenBeak here]]

[[center: [-[[Characters/{{Metroid}} Main Character Index]] | [[Characters/MetroidSamusAran Samus Aran]] | [[Characters/MetroidTheMetroids Metroids]] ([[Characters/MetroidMetroidPrimeAndDarkSamus Prime]]) | [[Characters/MetroidSpacePirates Space Pirates]] ([[Characters/MetroidMotherBrain Mother Brain]] | [[Characters/MetroidRidley Ridley]]) | '''X Parasites''' | [[Characters/MetroidGalacticFederation Galactic Federation]] |\\
[[Characters/MetroidTheChozo Chozo]] ([[Characters/MetroidRavenBeak Raven Beak]]) | [[Characters/MetroidBountyHunters Bounty Hunters]] | [[Characters/MetroidOtherAntagonists Other Antagonists]] | [[Characters/MetroidOthers Others]] | [[Characters/MetroidNoncanonicalCharacters Noncanonical Characters]]]]-]

* CoresAndTurretsBoss: Nettori is the core, with pollen-spraying plants being its turrets.

* ManEatingPlant: Its "turrets" also function as pitcher plants that slowly digest Samus if she falls in. [[CripplingOverSpecialization Not being an insect or tree rodent of any]], simply holding down the jump button solves the problem for her.
* OneWingedAngel: It becomes a Beam Core-X, allowing it to use its plasma beam to attack in addition to ramming while rendering its outer carapace immune to Samus's weapons.

* WaterfrontBossBattle: Nettori itself hangs passively above the water, but the water has deadly plants growing in it which attempt to eat you alive and make it difficult to get out of the water if you fall into it.

* PowerParasite: Since Power Suits are OrganicTechnology, X have repeatedly shown the ability to steal and use Chozo powerups for themselves, forcing Samus to absorb them in turn to get the ability for good. Even putting the SA-X aside, most bosses in ''Fusion'' (as well as a few bosses in ''Dread'') are shown actively incorporating whatever power they absorbed into their new body, sometimes in a logical way (the one who uses the Morph Ball turns into an [[VideoGame/Metroid2ReturnOfSamus Arachnus]], which is already capable of curling up and rolling around), sometimes turning into aberrations like a GiantSpider doing backflips even without limbs (the Yakuza, having taken the Space Jump) or a hermit crab summoning clean geometrical patterns made of explosions (the Golzuna, who holds the Cross Bomb).

* GreaterScopeVillain: For the entire series, especially ''Metroid II/Samus Returns'', as the Metroids were created exactly to counter their infestation of [=SR388=]. And the X in general are much more dangerous to life due to their higher intelligence and being harder to fight off. Everything in the series can be traced back to the X in some form or fashion.

* GodzillaThreshold: The existence of the X [[spoiler:and the Federation's [[TooDumbToLive desire to study and use them]]]] is one of the biggest thresholds in the entire series. As mentioned, they were the entire reason the Metroids exist, which themselves are a dangerous threat to the galaxy, as they were created by the Chozo to combat the seemingly NighInvulnerable threat. Samus considers detonating the BSL research station, [[HeroicSacrifice even at the cost of her own life]], to be worth it to destroy the X onboard. Adam's response is that this ''doesn't go far enough'' and that the station should be [[ColonyDrop rammed into the planet below as it explodes]] in order to be well and truly rid of the X.

* AquaticMook: They are more than up to the task of mimicking aquatic creatures [[note]]Evirs, Owtches, Powamps, Scisers, Skulteras, and Yards[[/note]] to fight you when you're in the underwater sections of the B.S.L station. They will also combine Space Pirate DNA with Skultera DNA to make Aqua Zebesians that have no trouble swimming right up to you and taking chunks out of your health.

* BetterToDieThanBeKilled: The X has a pretty high chance to run after their corporeal form is destroyed, but they'll usually stay and try to fight Samus to death.

** Beyond a Metroid, the only sources of power that have been shown capable of killing an X include [[spoiler:[[AMoltenDateWithDeath the heat of a planet's mantle]] (and maybe not even that), a [[EarthShatteringKaboom planet-destroying explosion]], and the [[WaveMotionGun Hyper Beam]], a weapon so powerful it can tear apart mountains and reduce several hundred tons of fortified steel capable of resisting power bomb explosions to dust in less than a second of sustained fire. And ''even then,'' the X can still mimic forms capable of surviving molten heat and could even assume forms that could survive multiple seconds of sustained Hyper Beam fire, the latter seen with Raven Beak X.]]

* TheSoulless: Samus muses that the X can mimic the knowledge, powers, memories, and abilities of their victims perfectly, but they cannot copy the soul. This is supported by the X driven by a mindless desire to consume everything despite being fully capable of planning and going against instinct to solve problems. [[spoiler: Though this does implicitly get called into question by the actions of Quiet Robe at the end of ''Dread''.]]

[[caption-width-right:350:[[labelnote:Click here to see its mutated form]] https://static.tvtropes.org/pmwiki/pub/images/sa_x_mutated.png[[/labelnote]]]]

* ArtificialBrilliance: During the final showdown with it, the SA-X will notice your fighting patterns and adapt to them. If you try to evade its attack often by jumping over it, it will soon answer with a Screw Attack right in that direction, hanging from ledges will lead to it shooting you down with missiles so that the tremor drop you down. If you keep evading the Ice Beam attacks with the Screw Attack invulnerability to projectiles, it will start to dive you with its own Screw Attacks, which deal high collision damage. Albeit, two colliding screw attacks will also deal damage to it and it reacts to being damaged the same way each time. Once one finds comfortable way of doing damage and avoiding the inevitable counter attack the SA-X will quickly crumble.
* ArtificialStupidity: Despite the fact that the SA-X is the most powerful enemy in all of ''Fusion'', and despite the X's ability to copy any organic body part, [[https://www.youtube.com/watch?v=M98esMR3Q-g it]] [[https://www.youtube.com/watch?v=6JL03zssV5o apparently]] [[https://www.youtube.com/watch?v=1QnBpf88pRI lacks]] [[https://www.youtube.com/watch?v=Q7Ap14qUORo&t=18s a brain]]. The SA-X has absolutely horrid looping programming, to the point most can be exploited for humor. Power Bombs in particular seem to completely throw its programming into an infinite loop when Samus isn't in a room needing the Power Bomb to advance. This can be exploited in the boss fight with the SA-X. There is a ramp above the recharge station in the room where you must send the space station into [=SR388=]. Continuously charging and shooting SA-X will cause her AI to instinctively charge at you with a Screw Attack in an infinite loop as long as you know what to do.

* AttackAttackAttack: While it has Samus' weapons and dexterity, it's otherwise a completely feral creature. All of its time is spent idly roaming the halls of the station in search of prey, and when it encounters anything objectionable its only strategy is to charge in and start blasting. Usually this is enough, but two SA-X instances meet their ends when their aggression leads them to pick suicidal fights with metroids.

* BoringButPractical: It only has 3 attacks, the Ice Beam, Screw Attack and a rare super missile (which it only fires after hitting you with the Ice Beam). However, all of them hit like a truck, are very fast and the SA-X can deploy them in a plethora of adapting patterns, making it all the same an extremely challenging opponent, since your charged beam and screw attack are only effective ways of damaging it. Also true of its Armored Core form, which can only chase you and shoot at you with the Ice Beam. Doesn't do much else, but its hard to hit its vulnerable eye with a missile, and its weapon ''is still the Ice Beam.'' Like all Core-X, the Plasma Beam will produce numerous X for which to regain health and ammo, and as a Beam Core-X it moves at a glacial pace, so if the player can survive for half a minute the challenge amounts to successfully aiming and timing diffusion missiles.
* ClippedWingAngel: When it takes too much damage it transforms into a gigantic hulking monster. It packs a serious punch but can be destroyed in only three charged shots and its laughably easy to evade its only attack, which is jumping around.
** However, after this form goes down, it turns into the Beam Core-X, which can chase down Samus and use the ice beam to attack, as well as being immune to Samus's weapons unless she targets the eye while it prepares to attack. In this final desperate form, this trope is downplayed, as while it is definitely less difficult than the fight while the SA-X had its stable Power Suit form, the arena where the SA-X is fought makes the timing of hitting the eye when it opens difficult[[note]]The flat portion of the arena is just wide enough to let the Core ready the beam ''while not'' giving Samus enough space to cleanly shot at it and trying to aim at it anywhere else or in the air else is nigh-impossible due to the eye turning to face Samus[[/note]] not to mention ''it is still the fully powered ice beam'', which instantly rips off 2 entire health tanks. After the brutal first part of the fight, the core portion can be especially stressful as Samus is likely low at health already and landing a hit on it demands her to expose herself to a direct ice beam.

* TheDreaded: Samus and the player spend most of Fusion hiding from it and the rest fleeing in terror. It's only in the final stretch of the game that Samus becomes strong enough to stand even a ghost of a chance against it and even then the FinalBattle with it is widely regarded as one of the toughest fights in the entire series.

* GlassCannon: Compared to most other final bosses in the series such as Mother Brain, Metroid Prime, Dark Samus, The Metroid Queen, or Proteus Ridley, the SA-X isn't very durable[[note]]the exact amount of shots you need to kill its first form varies a bit as if you manage to hit it while frozen or in certain angles as the Wave Beam will stay inside it for longer, doing way more damage. For the best of speedrunners it goes down in 4 or 5, but it usually takes 11-13[[/note]], being comparable to the unifinished Ridley robot without the benefit of a guardable weak point. However, its nature as a MirrorBoss with a [[MyRulesAreNotYourRules cheating screw attack]] gives it very high agility, making it harder to hit. It also packs an ''extremely painful'' punch, forcing the player to be careful. Its main projectile attack, the Ice Beam, is not easy to avoid without using Screw Attack (which stops you from starting a charge beam, and it can be broken by the SA-X screw attack at the cost of some of its health) and it instantly blows up ''2 whole energy tanks''. Contact damage with is also very high and it will constantly try to run you down with its own Screw Attack (especially after it notices your own attack patterns) which is as devastating as the Ice Beam. This is further pronounced in its last two desperate forms, neither of which last for long (its monster form goes down in 2 or 3 hits and its core in 6) but they blow up several energy tanks with any of their attacks. Just remember that you can't start a charge with a screw attack but can keept a charge with one and try to beat the glass cannon to the trigger.

** Indeed, the SA-X even uses Samus' Metroid battling tactics against her; its standard procedure is to freeze its target with the ice beam and then follow up with a super missile.

* MirrorBoss: More so than even Dark Samus, as while Dark Samus will use heavy modifications of Samus weapons, directly weaponize phazon and various things Samus simply can't obtain on the ''Prime'' series, the SA-X's arsenal is ''literally'' made up of Samus stolen weapons. The first portion of the final fight with it is this trope in full effect and is known to be one of the toughest fights in the franchise. Averted once its first form breaks, as it will pull into the classic X bag of tricks by turning into a hulking monster and then finally into its core form.

* NoSell: It has Samus’s fully upgraded armor on top of adding its own X brand modifications, so nothing can even touch it until the final battle with it. Ice Missiles can stun it for a single second but they don't do any damage. Even during the final battle, you can ''only'' hurt it with a fully charged shot of the Plasma Beam. You can't feed it missiles like most other bosses, so while if it doesn't need that many attacks to bring it down, charging and aiming all of them while it rains you down with the hardest hitting attacks in the game is very difficult.

* SecretAIMoves: Downplayed, but the SA-X can do a screw attack without actually having to jump, which is something Samus never could. Notably, it can do it on a straight line, which is deadly during the FinalBattle.
* ShadowArchetype: To Samus, literally and figuratively. The SA-X is basically if Samus chose to [[JumpingOffTheSlipperySlope jump off the slippery slope]] by killing the baby Metroid rather than spare it, and by doing so ensuring the complete extinction of all Metroids and allowing the X Parasites to cultivate.
* ShapeShifterSwanSong: It loses its hold on its mimicry of Samus when it takes too much damage, regressing into a bestial abomination with traits taken from her armor and very likely the hornoad the original parasite was infesting before it ever encountered Samus and finally breaks down into its core form.
* SuperToughness: Unlike Samus herself, the SA-X is completely invincible to beams, missiles, super missiles, and power bombs. Only the penetrating effect of the plasma beam can harm it, and even then only a fully charged shot has any effect. Ice missiles can freeze it solid, but since it can thaw out faster than any other foe in the franchise, it's not much help.

* SwallowedWhole: This is actually a dumber strategy than spitting Samus out in this case, as its digestive damage is pretty low and its insides are vulnerable to morph ball bombs. Still, not getting swallowed feeding it missiles is a better strategy for Samus.

-> ''"This sector is home to a very large creature the researchers call Serris. It is capable of moving and attacking at ultra-high speed. The more senseless and widespread destruction here may be attributable to Serris. No doubt the SA-X released it, but I can't be sure why yet. Serris has returned often to the breeding tank here. Its natural behavior must be to go back to it periodically. It's a valuable specimen, but you have been authorized to terminate it. If you don't, it may invade other sectors."''

* DoubleJump: It's capable of using Space Jump after losing its legs. Like Zazabi and Serris, it's unknown if this is a natural ability or if it is somehow using the actual power-up due to the X.

* TookALevelInBadass: Compared to ''Fusion'' anyway, whereas the Zombie Researchers were TheGoomba and by far one of the weakest enemies in the entire Metroid series if not for their ResurrectiveImmortality ability; the Chozo Zombies are ''substantially'' more durable and able to do a surprising amount of damage very quickly if allowed to close their proximity. Possibly justified by the Chozo Zombies being made from [[ProudWarriorRace Mawkin warriors]] instead of [[PunyEarthlings frail human scientists]].

* ClothingAppendage: Its "armor" is integrated into its body, though unlike Samus, it's also copying Samus' human form underneath (or at least her face).

* TakingYouWithMe: It planned to detonate the entire station in a gambit to kill Samus, an act that would have killed itself and all other X on the station, but [[TheNeedsOfTheMany ensure the survival]] of its species on SR388.

* TakingYouWithMe: It planned to detonate the entire station in a gambit to kill Samus, an act that would have killed itself and all other X on the station.

* EvilOnlyHasToWinOnce: The main threat regarding the X and why the Chozo were so desperate to deal with them, to the point that they created a bioweapon almost as powerful as the X; the outbreaks on [=SR388=], the BSL research station, and ZDR were only the ''start'' of what the X wanted. The X are, on a genetic level, predisposed towards propagating their species and ensuring their own survival. They have no other motive, and nothing short of a Metroid can truly hamper them for long, making any X outbreak a ''living'' GreyGoo scenario. All the X need to more or less completely consume ''everything'' in the universe - and what they intentionally set out to get in the BSL research station and on ZDR - is a form possessing memories that would allow the X to spread off-world and throughout the galaxy, and a spacefaring vessel they could then use to exploit those memories.

* EvilOnlyHasToWinOnce: The main threat regarding the X and why the Chozo were so desperate to deal with them that they created a bioweapon almost as powerful; the outbreaks on [=SR388=], the BSL research station, and ZDR were only the ''start'' of what the X wanted. The X are, on a genetic level, predisposed towards propagating their species and ensuring their own survival; they have no other motive, and nothing short of a Metroid can truly hamper them for long, making them a ''living'' GreyGoo scenario. All the X need to more or less completely consume ''everything'' in the universe - and what they intentionally set out to get in the BSL and ZDR - is a form that had memories that would allow the X to spread off-world and throughout the galaxy, and a vehicle they could use to exploit those memories.

* FromNobodyToNightmare: A minor example, but how it's introduced. It initially starts as a Muzby-X. Defeating it causes it to mutate into a Goliath. Defeating ''that'' causes it to transform into Golzuna, a full-fledged boss.

* ItsTheOnlyWayToBeSure: Once the X have been broken quarantine on an ecosystem, it can be safely assumed that the entire planet is done for. Due to its ability to mimic anything, down to their appearance and memories, there is no way to tell what is or isn't an X, so anything and everything within its reach needs to destroyed for the safety of the galaxy. Since this spread can occur within ''minutes'', that basically means anyone who isn't separated by extreme distances or hermetically-sealed environments cannot be allowed to escape offworld, as the whole mess starts all over again if even a single X ever finds its way into space.

* TheEndOfTheWorldAsWeKnowIt: This is more or less what happened when the X made a comeback on SR-388. Without a predator to stop them, the X devoured all life on the planet. [[spoiler:It's also what would have happened elsewhere had the Galactic Federation gone through with their plans to capture the SA-X.]] [[spoiler:After escaping Elun in ''Dread'', they overrun ZDR within ''minutes'' of getting loose.]]

Parasites that evolved on [=SR388=], where they began to greatly endanger the planet by absorbing the biomass of other organisms, copying the victims, and throwing the ecosystem out of balance. These creatures were such a massive threat, the Chozo intervened by giving them a predator: The Metroid. Metroids were their main predator, until all of the Metroids were wiped out on [=SR388=], allowing the X to make a recovery in their population and return in ''VideoGame/MetroidFusion''.

* AmbiguouslyEvil: At first, they are assumed to be AlwaysChaoticEvil, [[spoiler:Quiet Robe's doppelganger displays odd behavior at the end of ''Dread'', willingly allowing itself to be absorbed by Samus, presumably to "reverse" her transformation into a metroid.]]
* AquaticMook: They are more than up to the task of mimicking aquatic creatures to fight you when you're in the underwater sections of the B.S.L station. They will also combine Space Pirate DNA with said aquatic mook DNA to make mer-pirates that have no trouble swimming right up to you and taking chunks out of your health.

* KillAndReplace: The X had already done this to the fauna of [=SR388=] prior to the events of ''Fusion'', allowing them to infiltrate the orbiting research station when the researchers collected X mimicking biological samples from the planet's surface. [[spoiler:This also spelled the doom of the Mawkin Tribe, when an X Parasite impersonated one of Raven Beak's soldiers and started a new outbreak on ZDR.]]

* SpikesOfVillainy: X seem to add them to a lot of the things they mimic.
* ThereIsAnother: The X are so destructive that [=SR388=] and the B.S.L station were detonated entirely just to get rid of them before they could spread. The events of ''Dread'' kick off with a video transmission of an X Parasite on Planet ZDR being sent to the Galactic Federation, which causes them to send seven of the E.M.M.I. units, and later Samus, to investigate the planet. [[spoiler:It turns out that the X Parasites had gotten off of [=SR388=] a long time ago, hitching a ride with the Chozo returning home to ZDR. They wiped out the Mawkin tribe and were sealed away by Raven Beak before they could infect him.]]

* MadnessMantra: Upon assuming Quiet Robe's form, it repeats his last words to her, "I am counting on you", over and over as it reactivates the E.M.M.I.s.