Hidden Phantom

Hidden Phantom, or simply Phantom, is a character in the Mega Man Zero series. Phantom is the leader of the Zan'ei Army (斬影軍団) with the title of Inshō Phantom (「隠将」ファントム). Phantom's schematics were based on that of X's capabilities of stealth. He is one of Copy X's Four Guardians.

Design
Like his siblings, Phantom's armor is based on that of his biological origin, X, with thematic alterations. Phantom's armor is colored black. His design is based on that of a ninja, having ninjutsu skills and making use of shuriken, kunai and katana to attack, as well as using illusions and substitutes to conceal himself. He is thus aptly named for his dark nature and ghostly movements. A white mask covers the upper half of his face, and he wears a red two-tailed cape on his back.

Phantom is the only member of the Four Guardians not to display an Armed Phenomenon form, having sacrificed himself in the first game before such transformations were revealed. Although he doesn't appear in Mega Man Zero 2, the Mega Man Zero Official Complete Works contains concept art which depicts Phantom's Armed Phenomenon form (which is a bat/wraith like form - see Gallery).

Powers and Abilities
As a Reploid clone of the original X, Phantom is an extremely powerful warrior in his own right. Having his design based around X's stealth capabilities, Phantom's fighting style and abilities revolve around various ninja-like arts, such as stealth, deception and misdirection which he combines with a matching set of tools such as smoke bombs, a katana-like blade and a large shuriken which can break apart into several kunai and serve as a flying platform. His EX skill makes the whole background dark and throw 4 kunai in different directions. Together with the fact that he is the first boss in the first Mega Man Zero game with three health bars, arguably makes Phantom one of the most difficult bosses in this game.

Armed Phenomenon
The only Guardian who never displayed this ability due to his untimely death, a piece of concept art shows that Phantom is also capable of using the Armed Phenomenon to assume a more powerful form, in his case one of a large wraith/bat-like form. The concept art also shows that he is able to aim and fire the tips of his wings as giant blades and close his wings to assume a large, kunai-like form.

Personality
Phantom has a calm, quiet demeanor. His major trait is his unwavering allegiance to his "Master X", displaying more loyalty than his three counterparts (none of whom were willing to sacrifice their lives in order to protect Copy X, possibly since they knew he was not really their "master" only a flawed replica of him). Phantom has no mercy for those who oppose Neo Arcadia. His sacrifice may be considered admirable, despite the flawed nature of its cause.

History
At some point, Phantom and the other three Guardians were cloned from X's DNA; for exactly what purpose is unknown (and exactly when is unknown), though it may have simply been to be bodyguards for X as they have been for around a century in Neo Arcadia. At some point, the four became military generals of Neo Arcadia, responsible for the overall safely of its inhabitants, both humans and Reploids. Phantom became the leader of the Zan'ei Army, Neo Arcadia's stealth units and anti-Resistance intelligence unit.

Mega Man Zero
Phantom's first appearance was to fight against Zero in a factory captured by the Resistance. Zero defeated him, but Phantom turned the tables when he informed Zero that he had planted bombs all over the factory. Zero found them and disposed of them, and later defeated Phantom's closest apprentice, Hanumachine.

When Phantom confronted Zero again in Neo Arcadia's Core, he was again defeated, but this time self-destructed in hopes that his explosion would harm Zero and protect his master. Zero escaped, however, and went on to defeat Copy X. After his death, Phantom's Cyber-elf entered the Cyberspace, where he would encounter Zero in his third adventure.

Mega Man Zero 3
If Zero entered Cyberspace in the Sub Arcadia Level, a secret door would appear that would lead him into a confrontation with Phantom. In Cyberspace, the world where all data is sent along with Reploids after death, Phantom learned all truths about the past. He claimed Zero never had the strength within him to be a hero. However, after being defeated by Zero, Phantom realized Zero's power and encouraged him to cross blades with Omega to prove himself once and for all.

After his battle with Zero, Phantom met up with Cyber-elf X, with whom he went to help the two guardians, Fefnir and Leviathan, who were reaching critical state from their battle with Omega earlier on in Mega Man Zero 3. X helped the two recover, as Zero started his battle with Omega, convincing them, and later Harpuia, to help Zero. Phantom didn't appear to help, due to his status as a Cyber-elf. The other Guardians were destroyed by Omega's explosion, but Zero was protected by the Dark Elf, who shielded him from the blast with her own body.

Mega Man Zero 4
Phantom, like the rest of the Guardians, doesn't appear in this game. Tech Kraken, however, is a pupil of his, and has joined the Einherjar Eight Warriors for an opportunity to avenge Phantom.

Mega Man ZX series
Phantom reappears in Mega Man ZX as the Biometal Model P. He is still fiercely loyal to X, who became Model X. When used by Vent or Aile, Models P and X combine to become the stealth-oriented Model PX. In Mega Man ZX Advent, Biometal P is used by Siarnaq.

Other Appearances

 * In Mega Man Zero 3, Phantom has a mini-game where the player needs to jump between shurikens without falling, and avoid spiked balls. If the player misses a shuriken or gets hit, they'll fall from the sky to the ground.
 * Phantom also appears in the Rockman Zero manga.
 * Phantom, along with X and the other three Guardians are depicted in an illustration viewing the descent of Ragnarok after Dr. Weil's defeat in Zero 4, from the Vile's Incident booklet included with the Remastered Tracks Rockman Zero Physis soundtrack. Interestingly, Phantom and the other Guardians, are shown with updated armors (in their Cyber-elf forms) with capes matching their armor in color, each with an X symbol on the back. In Mega Man Zero Official Complete Works, developers behind the game state that this piece is nothing more than fan art.

Trivia

 * Even though Mega Man Zero has broken the tradition of defeating a boss at the end of a mission, Phantom still stands out as the only boss in the game that is fought at the very beginning of the stage. This is later carried on with Argoyle and Ugoyle in Mega Man ZX Advent.
 * Phantom is the only returning boss in Mega Man Zero 3 that is not featured in the storyline. He was fought as a secret boss instead.
 * Ironically, even though Phantom has shown himself to be one of the more noble enemies in the Zero series, the Mega Man Zero 3 database claims that he is an evil Dark Lord.
 * A plausible reason why Phantom is named an "evil lord" in his Mega Man Zero 3 Secret Disk is that Zan'ei can be translated as "Cruel Phantom", which is odd because of his nature. It is possible this was a mistranslation overseas.
 * Surprisingly, out of any of the other Guardian's divisions, members of Phantom's Zan'ei army are fought most often in the Zero series (five of them: Hanumachine, Phoenix Magnion, Burble Hekelot, Hyleg Ourobockle, and Tech Kraken), while the leader, Phantom himself, appears physically in only two games, compared to the other Guardians, who are in three.
 * Hidden Phantom bears a resemblance to Shadow Man from Mega Man 3: Both are ninjas, they have extreme fighting skills, and they can use shuriken (thowing stars).
 * Oddly enough, in another Capcom's game, Knights of the Round, there is a boss called "Phantom", a thief dressed in black, very quick and deadly.
 * Phantom is the only guardian which does no transformed to his Armed Phenomenon form.