History Videogame / MegamanX4

* GameMod: The 1998 PC version has the Final Weapon project, a mod that not only restores the game's Japanese voice-overs, it also retranslate the game's original Japanese script, aims to update the game's soundtrack with higher-quality equivalents from the Capcom Music Generation albums, higher quality 480p [=FMVs=], and implements input commands for Zero's special techniques in the pause menu.

* BittersweetEnding: While X's ending is only somewhat bittersweet, Zero's ending really qualifies for this. [[spoiler:Sigma is once again defeated and the Final Weapon is destroyed along with him, but the Repliforce fiasco has taken untold lives, not just the presumed thousands in the Sky Lagoon crash and the subsequent conflict, but including all of the newly introduced major characters such as Iris, Colonel and General (the former two being killed by Zero, the latter performing a HeroicSacrifice to destroy Final Weapon). Also, Zero tragically rediscovers his former Maverick history as the unwitting source of the Sigma Virus. Even after he saves the day, he even wonders if all reploids will go Maverick after all. Whereas [[VideoGame/MegaManX1 the first]] [[VideoGame/MegaManX2 two games]] ended on a triumphant note and [[VideoGame/MegaManX3 the third game]] on a mildly bittersweet note, this game really ended in a much more melancholy way.]] It also retroactively turns the ending of ''X3'' into a DownerEnding; [[spoiler:we find out in this game that despite his efforts, Dr. Doppler's antivirus is useless against the Sigma Virus in the long run, the latter finding a way to overcome it, and that Sigma didn't even ''need'' to infect others to incite another war, but instead pull strings and turn the Reploids against each other. Doppler's potential HeroicSacrifice was all for nothing.]]

* AIBreaker: When playing as X, All of the special weapons when used against the bosses weak to them. It's possible to defeat all eight of the main bosses in the game without taking damage, because getting hit with their weakness tends to reset their attack pattern, and then you just hit them again the instant their invincibility frames are over.

* AIBreaker: All of the special weapons when used against the bosses weak to them. It's possible to defeat all eight of the main bosses in the game without taking damage, because getting hit with their weakness tends to reset their attack pattern, and then you just hit them again the instant their invincibility frames are over.

* InstantAwesomeJustAddDragons: [[WarmupBoss Eregion]] and Magma Dragoon.

[[ExtyYearsFromNow In the year 21XX]], years following the Doppler rebellion, a global Reploid military called "Repliforce" is formed to help combat the constant Maverick uprisings. However, they consistently fail to protect humans, causing humanity to distrust them and their military might. This causes tension between Zero and his sweetheart Iris, who is the sister of Colonel, an influential leader in Repliforce.

[[ExtyYearsFromNow In the year 21XX]], years following the Doppler rebellion and the revelation of the existence of the Sigma Virus, a global Reploid military called "Repliforce" is formed to help combat the constant Maverick uprisings. However, they consistently fail to protect humans specifically, leading to humanity distrusting them and their military might. This causes tension between Zero and his sweetheart Iris, who is the sister of Colonel, an influential leader in Repliforce.

[[ExtyYearsFromNow In the year 21XX]], years following the Doppler rebellion and the revelation of the existence of the Sigma Virus, a global Reploid military called "Repliforce" is formed to combat the constant Maverick uprisings. However, they consistently fail to protect humans specifically, leading to humanity distrusting them and their military might. This causes tension between Zero and his sweetheart Iris, who is the sister of Colonel, an influential leader in Repliforce.

One day, the aerial city Sky Lagoon is sabotaged by Mavericks, causing it to crash to the ground; with Repliforce suspiciously in the area, the Maverick Hunters request Colonel disarm his men and come in for questioning. However, Colonel refuses out of pride and contempt for human government. This incident is the last straw, and the head of Repliforce, a giant Reploid named General, launches a coup d'état to start a nation only for Reploids. This immediately causes the entirety of Repliforce to be labeled as Mavericks by the human government, forcing the Maverick Hunters to turn against them.

[[ExtyYearsFromNow In the year 21XX]], years following the Doppler rebellion and the revelation of the existence of the Sigma Virus, a global Reploid military called "Repliforce" is formed to combat the constant Maverick uprisings. However, they consistently fail to protect humans specifically, leading to humanity distrusting them and their military might. They also occasionally butt heads with the Maverick Hunters, who had been the sole fighters of Mavericks up until this point. This has caused tension between Zero and his sweetheart Iris, who is the sister of Colonel, an influential leader in Repliforce.

[[ExtyYearsFromNow In the year 21XX]], years following the Doppler rebellion and revelation of the existence of the Maverick Virus has led to the creation of a global Reploid military force named ''Repliforce'' to combat the constant Maverick attacks and uprisings. However, they are distrusted and feared by humans for their military power, destructive tactics and inability to protect humanity from the ever rising Maverick attacks. Some time before the game, Zero got to know Iris, the sister unit of one of the Repliforce's leaders only referred as The Colonel. One day, the aerial city Sky Lagoon is suddenly attacked, causing it to crash to the ground. With the Repliforce in the area, they're suspected to be responsible and the Colonel is asked to disarm his men and come in for questioning; however, he refuses due to his pride and his contempt for the human government. To make matters worse, the Repliforce General launches a coup d'état to start a nation only for Reploids, which immediately causes the entirety of Repliforce to be labeled as Mavericks by the human government, forcing the Maverick Hunters to turn against their allies.

* ArrogantGodVsRagingMonster: It's revealed that [[spoiler:Sigma and Zero fought before the former went mad and became the series BigBad and the latter becoming a Maverick Hunter. Before X1, Sigma was the noble commander of the Maverick Hunters and the most powerful Reploid built at the time. Once he learned of a "Red Maverick" wrecking havoc and killing Reploids, he voluntarily set out to take care of him on his own to prevent more lives being lost. Zero, the [[TheBerserker Red Maverick]] who was built by Dr. Wily centuries prior, had a program error in his brain that make him violent to anything that moved, thus he showed no fear or hesitation as he charged at the more experienced Sigma in a blind rage. For a while, they were even matched, with Sigma having a slight edge, until Zero gained the upper hand and savagely beat Sigma until his arm was ripped off, and half his was torn. Had the Wily symbol, which acted a fail-safe, not caused Zero enough pain to make him stop, Sigma would have lost his life. Though he won the fight, this event led to Sigma being infected by the Maverick Virus due to being close proximity to Zero.]]

* GuideDangIt: Are you wondering why Web Spider is not affected by his weakness, Twin Slasher? Here's a hint the game never tells you about: try hitting his web with ''both projectiles''.

* AccentUponTheWrongSyllable: "Storm Owuhl!"

* ShadowedFaceGlowingEyes: [[spoiler:Sigma's first has a pretty clear parallel to the grim reaper by invoking this trope with glowing yellow eyes from a face hidden by a dark cloak, while also floating and carrying around a huge scythe. Luckily for X & Zero, that robe is flammable, and they have [[KillItWithFire Rising Fire and Ryuenjin respectively]].]]

* Cyber Peacock, gives [[PlayerGuidedMissile Aiming]] [[FrickinLaserBeams Laser]] to X, and [[SmartBomb Raku]][[GroundPunch houha]] to Zero; is weak to Soul Body/Ryuenjin.

* DesignatedLoveInterest: Iris to Zero; they got together sometime between ''VideoGame/MegaManX3'' and this game, and don't share much romantic screen-time in the game proper [[spoiler:before Iris's death]].

* WhamEpisode: [[spoiler: This is the installment of the series that asks [[WhatMeasureIsANonHuman "What measure of non-human]] [[RidiculouslyHumanRobot are Reploids?"]] Whereas before the X and Zero's enemies had gone Maverick due to a virus, now they are required to face off against their former allies, the Repliforce. Rather than victims of a virus, Repliforce have simply chosen their own way, independent of the will of their human creators. Their move to create a place of their own, for Reploids only, doesn't even necessarily threaten harm to humankind; it's simply that a group of Reploids acting entirely independent of their human creators causes humanity to label them Mavericks ''as a whole'' in fear of what their freedom might mean. Repliforce's violence is a response to the perceived injustice of this situation, initially begun as a matter of self-preservation and escalating on both sides from there. In the aftermath of this conflict, X begins to seriously worry that one day even he will go Maverick; meanwhile Zero's reality is shattered when he discovers he ''was'' a Maverick previously. Both of them begin to grapple with the possibility that Reploids may eventually, perhaps inevitably, become self-determining to such an extent that the Maverick label will ultimately apply to any and every Reploid who thinks and acts for themselves. This theme remains prominent throughout the rest of the X series, and is further explored and taken to its logical conclusion in the ''VideoGame/MegaManZero'' series.]]

* WhamEpisode: [[spoiler: This is the installment of the series that asks [[WhatMeasureIsANonHuman "What measure of non-human]] [[RidiculouslyHumanRobot are Reploids?"]] X and Zero are no longer facing Reploids turned Maverick by way of a virus, but allies branded as enemies because they have chosen their own path, with their violence being a response to the perceived injustice of their situation. By the end of this conflict, X begins to seriously worry that one day even he will go Maverick, and Zero's reality is shattered when he discovers he ''was'' a Maverick previously. Both of them begin to grapple with the possibility that Reploids may eventually, perhaps inevitably, become independent to such an extent that the Maverick label will ultimately apply to any and every Reploid who thinks and acts for themselves. This theme is ongoing throughout the rest of the X series, and is further explored and taken to its logical conclusion in the ''VideoGame/MegaManZero'' series.]]

* WhamEpisode: [[spoiler: The installment of the series which asks the question of [[WhatMeasureIsANonHuman "What measure of non-human]] [[RidiculouslyHumanRobot are Reploids?"]] This time, X and Zero must face off against not Reploids turned Maverick by viruses, but allies turned enemies who have chosen their own path - and violently in response. By the end of this war, X harbors questions of whether if even he will go Maverick, Zero's reality is shattered when he discovers he was once a Maverick, and both come to show the inquiry whether if Reploid kind will ultimately become so self acting that becoming "Maverick" and its label as a crime will be a natural and ultimately conflicting development in the future.]]