"Nightmare" redirects here. For the Mega Man Battle Network series virus, see Nightmare (virus). For the weapon, see Mega Man X DiVE/Weapons.

The Nightmare Phenomenon, occurring throughout Mega Man X6, is created by Gate by analyzing a piece of Zero's DNA he found in the remains of Eurasia.


The Nightmare is an artificial entity shown to take on multiple forms. It can be described as both a virus and as a phenomenon.

The Virus

"I found out what the Nightmare is... The Nightmare is an artificial virus. It infects Reploids and rewrites their DNA and AI programs, immobilizing them. At worst, even their appearance changes. We don't know exactly as our analysis is not yet complete... But it is very similar to the Mavericks."

The viral form of the Nightmare vaguely resembles a Reploid, distinguished by its black and golden frame, a single large red eye on its head and flexible appendages patterned after DNA chains.

The Nightmare is designed to infect Reploids and immobilize them as it rewrites their DNA and AI programs. During the rewriting process, the Nightmare also inputs a certain code that allows control over the infected Reploid. The victims are modified to the point that even their appearance changes; however, there are cases in which the Reploid does not survive the aggressive intrusion.

The manner in which the Nightmare affects its victims is largely similar to the Sigma Virus; however, while a normal virus usually dies with the host, the Nightmare is strong enough to survive the Reploid's destruction. On the other hand, since its energy is so powerful and concentrated, it can be damaged and even deleted by regular weaponry, without the need of a special vaccine.

Upon its destruction, a Nightmare will drop an item called a Nightmare Soul. Gathering Nightmare Souls increases the player's Hunter Rank, and collecting at least 3000 of those before defeating all eight investigators will trigger a cutscene with Alia revealing the true nature of the Nightmare. Dynamo also demonstrates an obsession with gathering Nightmare Souls, expressing a desire of powering up with the DNA within them. Take note that only the first Hunter to achieve this will have his specific cutscene triggered as there are 2 versions of this cutscene available (one for X and one for Zero).

Many of the Rescuable Reploids in X6 are located dangerously close to the Nightmares, requiring the player to act quickly before the virus latches onto the Reploid's back and rewrites its DNA. Reploids modified by the Nightmare can no longer be rescued; they are lost forever, along with the reward the player would obtain from saving them. The infected Reploid and the Nightmare may still be destroyed, but the Nightmare will not yield a Nightmare Soul in this scenario.

The Phenomenon

"It shows Reploids a kind of "dream" for human beings... no. It's a "Nightmare". The Nightmare makes Reploids confused. In the worst case, they may malfunction or delete themselves."

The Nightmare has earned its name for its ability to produce nightmarish visions on Reploids. While advancing through stages, players will come across abnormal events that cannot be detected by Alia, indicating the presence of a "Nightmare phenomenon". The Nightmare is said by Isoc to confuse Reploids, leading them to behave erratically or even destroy themselves. Each stage from the eight Nightmare Investigators have a Nightmare phenomenon that is activated in other stages after playing through their stages:

Nightmare Bugs Nightmare Bug (ナイトメア・バグ) - A bug enemy that appears in the stages of Shield Sheldon and Blaze Heatnix after going through Commander Yammark's stage. More info below.
Nightmare Cubes Nightmare Cube (ナイトメア・キューブ) - An obstacle that appears in the stages of Metal Shark Player and Shield Sheldon after going through Ground Scaravich's stage. The red and brown ones can be destroyed with the Ground Dash and Sentsuizan, while the black and purple ones can only be pushed by these same attacks. Note that the red ones cause an explosion that can cause serious damage to the player when destroyed. For the cubes that cannot be destroyed whatsoever, purple cubes slide when struck while the black ones move a slight bit (however, the Ground Dash must be fired at point-blank to do so).
Nightmare Dark Nightmare Dark (ナイトメア・ダーク) - This phenomenon happens in the stages of Commander Yammark and Rainy Turtloid after going through Infinity Mijinion's stage. The screen will become pitch-black, with the only source of light being visible/semi-visible portions moving in a searchlight pattern. This greatly reduces visibility, increasing the difficulty of the stage by a sizable percent.
Nightmare Fire Nightmare Fire (ナイトメア・ファイア) -  This phenomenon is activated in the stages of Blizzard Wolfang and Infinity Mijinion after going through Blaze Heatnix's stage. Fireballs will fall from the top of the screen. Although it's mainly useless to do so, they can be destroyed by Magma Blade or Shoenzan. Of note, the optional area in Blizzard Wolfang's stage will only become available when Nightmare Fire is present to destroy an ice wall.
Nightmare Freeze Nightmare Freeze (ナイトメア・フリーズ) - This phenomenon is activated only in Metal Shark Player's stage after going through Blizzard Wolfang's stage. Some floors/surfaces are coated with ice and can be destroyed only with Ice Burst or Hyourouga.
Nightmare Iron Nightmare Iron (ナイトメア・アイアン) - Iron blocks that appear in the stages of Blaze Heatnix, Ground Scaravich and Infinity Mijinion after going through Metal Shark Player's stage. The blocks can only be destroyed using Metal Anchor or Rakukojin.
Nightmare Mirror Nightmare Mirror(ナイトメア・ミラー) - A silhouette form of X or Zero that sometimes appears in the stages of Rainy Turtloid and Blizzard Wolfang after going through Shield Sheldon's stage. It will have the form of a purple Zero if the player is using X, and the form of a turquoise X with Zero. Similar to the Zero Virus from Mega Man X5, they appear from nowhere and move in the player's direction. Its weakness is the Guard Shell.
Nightmare Wind Nightmare Wind (ナイトメア・ウインド) - Activated in the stages of Commander Yammark and Ground Scaravich after going through Rainy Turtloid's stage. A strong wind that pushes the player, accompanied by rain that indicates the wind's direction.

Other examples of Nightmare phenomena include:

Nightmare Ice Nightmare Ice (ナイトメア・アイス) - Rolling ice chunks that appear in Blizzard Wolfang's stage. They can only be destroyed with Metal Anchor, but it is better to avoid them as it requires several hits to be destroyed.
Nightmare Lasers Nightmare Laser (ナイトメア・レーザー) - Lasers in Shield Sheldon's stage. They're needed to complete the puzzles there, using the rotating reflective panels.
Nightmare Press Nightmare Press (ナイトメア・プレス) - The press in Metal Shark Player's stage.
Nightmare Rain Nightmare Rain (ナイトメア・レイン) - The acid rain in Rainy Turtloid's stage. Also appears in the Secret Lab when playing as X. It slowly drains the player's life gauge. They are often accompanied by platforms which recover health, Weather Analyze devices that are protected by shields, and cores that deactivate the shields.
Nightmare Random Nightmare Random (ナイトメア・ランダム) - Round and square rocks that appear in Ground Scaravich's stage and the 2nd of the final stages (where the player has to fight through two consecutive stages without resting). These seem to be the main enemies in Scaravich's stage other than the Totem Gates and Nightmare Viruses.

Nightmare Souls

A Nightmare Soul will spawn from a defeated Nightmare or Maverick. There are 4 types of Nightmare Souls known in this game, distinguished by color. They are:

  • Blue (Normal): Appears after a Nightmare has been destroyed. Worth 8 souls each.
  • Blue (Small): Appears when the Nightmare soul that has just been destroyed has not been obtained after 3 seconds. Worth 4 souls each. If the soul is not obtained after 5 seconds, it will re-spawn into a new Nightmare. Destroying it would not generate any Nightmare souls.
  • Green: Appears after defeating a Maverick Boss. The Nightmare soul will glow and descend onto the Hunter that is responsible for defeating it. Worth 200 souls each. It can also be obtained from Dynamo in the Secret Boss fights if the player hits him twice with his weakness (Meteor Rain or Ensuizan) in which he will drop one of those for the player to collect. Dynamo will drop a maximum of 3 such Nightmare Souls per battle, which means the player can at least net themselves 600 souls if they go into any stage and defeat Dynamo there.
  • Red: Replaces the green soul if the player took too long to defeat a Maverick Boss. Worth 100 souls each.

If the player has passed through a stage obtaining all the Nightmare Souls for that stage already, going through the same stage would not garner then any Nightmare Souls if they defeat those same Nightmares all over again. The only way the player can make them produce Nightmare Souls is to re-introduce a new Nightmare Phenomenon into that specific stage. Only then can the player defeat the same Nightmares there to obtain their Nightmare souls all over again to add to their Soul tally.


The Nightmare is a creation of Gate made through the use of Zero's DNA, using it to control the Reploids. Gate employs the Nightmare in a bid to create a Reploid utopia under his rule. Zero Nightmare, a clone of Zero, was made to make the public believe that Zero was spreading the Nightmare. Isoc used this explanation to rally Reploid volunteers to assist his "Investigators" in wiping out the Nightmare, when the actual intention was to gather victims for the Nightmare. However, the plan is thwarted by X and the real Zero; together, they defeat the Nightmares along with Gate.


Zero Nightmare

Zero Nightmare
Main article: Zero Nightmare

The Zero Nightmare (ゼロ ナイトメア Zero Naitomea) is a copy of Zero created by Gate with Zero's DNA.

Nightmare Mother

Nightmare Mother

Main article: Nightmare Mother

The Nightmare Mother (ナイトメアマザー Naitomea Mazā) is the boss of the first part of Gate's Secret Lab, two giant masses of Nightmare Viruses.


Nightmare Virus

The Nightmare Virus (ナイトメア・ウィルス Naitomea Wirusu) is an enemy found in almost every stage except the intro level and the first Secret Laboratory level. They can attack the player by shooting at them, or by getting close and touching them. If the player is playing on Xtreme difficulty, the virus can also disappear, reappear close to X or Zero, and charge at him. They leave behind Nightmare Souls when destroyed. If the player doesn't take the Nightmare Soul before it vanishes, the Nightmare Virus will regenerate, but only one time and it will not leave a Nightmare Soul when destroyed again.

If it's on the same screen with a Reploid in need of help, it will move in to try and possess them. If the Nightmare Virus is not destroyed or the Reploid is not rescued before the Nightmare Virus gets too close, the Reploid will turn Maverick (which somewhat resembles a zombie version of itself) and attack the player. If a Reploid holding an item is turned Maverick, the item will be lost forever.

Nightmare Viruses later reappear in Mega Man X DiVE, appearing in Zero Space. A card of this Maverick can also be obtained.

Nightmare Bug

Nightmare Bug (ナイトメア・バグ) is a bug enemy that flies near the player. Using normal attacks on them will only chase them off, only to reappear after some time. They can only be destroyed permanently by using the Yammar Option on them. They appear in Shield Sheldon's and Blaze Heatnix's stages and is activated after going through Commander Yammark's stage.

Nightmare Insect

Nightmare Insect (ナイトメア・インセクト Naitomea Insekuto) is a mantis enemy that appears in Commander Yammark's stage. If they are destroyed with any weapon other than the Yammar Option they will regenerate, leaving the player a quick chance to get by.

Nightmare Pressure

Nightmare Pressure (ナイトメア・プレッシャー Naitomea Puresshā) is the mid-boss of Metal Shark Player's stage. Presumably, it's the core of the trash compactor that antagonizes the player throughout the whole stage. It can shoot small balls, shoot with pink lasers, and can crush X like a compactor. Its weak point is the pink lasers. The compactor (but not the boss) returns in Gate's stage if the player chooses Zero.

Nightmare Snake

Nightmare Snake (ナイトメア・スネーク Naitomea Sunēku) is the name of five red Mechaniloid mid-bosses that appear in Blaze Heatnix's stage. They resemble a mythological creature known as Ouroboros, a snake that bites its own tail, making a circle. They can only be defeated by destroying the four green cores around their frame. They are weak to the weapon gained from Infinity Mijinion, Ray Arrow and Rekkoha. A charged Metal Anchor can take out the mid-boss in one hit, given a bit of positioning and luck. The Giga Attack of the Falcon Armor can take it out in one hit as well.

This mid-boss is considered to be one of the most annoying in the whole X series as there are six such enemies to destroy throughout the stage in which the player has to destroy five of to reach the stage boss. It is also worth noting that on Easy Mode, this mid-boss does not shoot its projectiles from its cores. Just prior to the boss fight, X reports seeing it and claims it was a Mechaniloid, although Alia notes that it isn't emitting a data signal, causing X to wonder whether it was actually a Nightmare and wondering who created it.


See also