Sigma

"Listen well, X. There are times when we Maverick Hunters cannot afford to hesitate in pulling the trigger. We must become both sword and shield to those who cannot protect themselves - that is our sworn duty. Never forget that!"

- Sigma, as "Commander Sigma"

"Your dedication to what you refer to as "justice" is what first got me thinking... I realized the imperfection of this world, and decided I must change it."

- Sigma

"You say you believe in justice. But that's not true. You've only been lead to think that. Nothing more!"

- Sigma

Sigma (シグマ), once referred to as Commander Sigma, is the main antagonist of the Mega Man X series. He serves as the final boss in all games except Mega Man X: Command Mission and Mega Man X8 if you play medium or hard mode (in the former, he makes no appearances and in the latter, Sigma is the penultimate boss). Created by Dr. Cain, Sigma was considered the finest of the Reploids and was the first leader of the Maverick Hunters; peace-keeping Reploids who defend humans against their renegade counterparts. Although he was once honorable, Sigma unexpectedly goes Maverick in the beginning of Mega Man X and rebels against humankind. He defects to the Mavericks and assumes the role of their leader. Under Sigma's command, the Mavericks grow into a legion dedicated to the extermination of the human race. Sigma instigates many of the destructive Maverick Wars, with the Maverick Hunters existing to crush Sigma and his minions.

Sigma appears as a bulky, bald humanoid in most of his forms; his most pronounced feature is a crystal on his forehead, and two parallel scars running through his eyes. He often produces a second form after his initial defeat in a game, which frequently has the head (or the crystal on it) as a weak point. Although he has been destroyed countless times, Sigma's programming always survives and builds himself a new form, ready to menace the world once again. It is implied that he grows more insane with each transformation. His primary enemies are X, Zero, and more recently, Axl.

Before Mega Man X
As the former leader of the Maverick Hunters, Sigma was originally the most advanced Reploid of his time. Dr. Cain implanted the latest circuitry designs into Sigma, which were theoretically supposed to prevent him from going Maverick. He was placed in charge of the 17th Elite Unit of the Maverick Hunters, and led them to victory multiple times.

One day, the Maverick Hunters received reports of an overwhelmingly powerful "Red Maverick" that has destroyed an entire squadron of Hunters (the Gamma unit). While investigating, Sigma, along with his unit, tracked it down to an abandoned laboratory. It is here that Sigma encountered Zero, the last product of Dr. Wily. Zero carried with him the malicious "Maverick Virus", which powered up his abilities and turned him into a "blood-thirsty god of destruction". Sigma was beaten badly by the maddened Zero, but managed to smash the energy crystal in Zero's helmet, which transferred the Virus directly into Sigma, infecting him. Zero lost consciousness, and Sigma limped away from the battle, ordering his men to take the body of Zero back for study. The virus began to mutate and adapt to Sigma's own programming, eventually fusing entirely with his mind to form the Sigma Virus, which when it infects a Reploid implants Sigma's mind into the victim.

The Day of Sigma
---

Mega Man X
Sigma's advanced circuitry seems to do its job, as he seemingly remains stable for months after the lab incident. He gradually succumbs to the virus inside of him and grows more volatile. Without warning, he leads a mass revolt among the Reploids, declaring total war on humanity, which is seen in the Day of Σ. Many Maverick Hunters follow Sigma out of loyalty, leaving Zero in charge of the organization. By this time, he has reformed and became a powerful Maverick Hunter. Mega Man X, the last creation of Dr. Light and the base model for every Reploid, decides to join Zero as thanks for saving his life. X and Zero battle through the Maverick regime, and it is X who finally destroys Sigma. But, though his physical body is scrapped, Sigma's "soul" (the Virus) survives. After the end credits roll, Sigma's face appears on a blue monitor and warns X that he will be back.


 * Sigma will first send his pet, Velguarder, to test of X's worthiness, before confronting him wielding a beam saber. Sigma's attacks consist mostly of dashing and wall jumping. In the game's remake, he also fires lasers from his mouth.  After defeating his first form, Sigma's head attaches itself to a canine-like, giant body called Wolf Sigma. This form attacks with claws, electricity, and fire; and can only be damaged by targeting its head.


 * In Mega Man X and its remake Mega Man Maverick Hunter X, it is shown that coupled with his goal to exterminate humanity, Sigma is also obsessed with unleashing X's full potential. Believing him to be the future of all Reploids..

Mega Man X2
Just as he promised he would, Sigma returns and assumes leadership of his Maverick forces. He gains a new body with the help of the X-Hunters, a trio of vengeful Mavericks who worship him, and becomes "Neo Sigma". He also oversees the "Unification" plot, which focuses on capturing and re-assembling the remains of Zero, whom he plans to reprogram to kill Mega Man X. But, since X managed to recover all of Zero's remains from the X-Hunters, Sigma was forced to make a copy of Zero's body that was not unlike Zero's Black Zero form; however, Zero arrives and destroys it completely before it could battle with X. Sigma then announces that he "knows Zero's secret", and that he's destined to serve him. It's unknown what exactly this secret is, but the dialogue suggests that it has something to do with Zero being created by Dr. Wily, and the possible origins of the Maverick Virus as Sigma calls him "the last of the Doctor's creations". Sigma attacks in his latest form, armed with clawed knuckles, but X thwarts his plans and destroys him again. This marks the first time Sigma's viral form is seen, as the Final Boss the game. Zero is then restored to his rightful place in the Maverick Hunters, and is given command of his own Special 0 Unit.

Mega Man Xtreme
Sigma uses a hacker named Techno to hack into the Mother Computer of the Maverick Hunter base. Noticeably more confident than previous times, Sigma taunts X after he's beaten the first time and even calls his defeat at the end of Normal Mode merely a retreat. It's only when he's defeated on Hard Mode that he seems to succumb to X.


 * Sigma has the same forms from the first Mega Man X, complete with the same weaknesses.

Mega Man X3
Sigma resumes his threat when he infects the Reploid scientist Dr. Doppler, who has developed a revolutionary new anti-virus to repel Sigma's influence. Sigma uses him to stage a revolt in Doppler Town, a Utopian city established on the principles of peace. Once Doppler is unmasked as a pawn, Sigma emerges in a heavily-armored form, "Kaiser Sigma". After his defeat for the third time, Sigma's "Soul" appears in the form of a wire-frame head and threatens to possess X's body to replace its own. After chasing X through the flaming wreckage of the base, Sigma finally corners him. If Zero did not end up critically wounded at any point during the game, which would have forced him to leave the war to X as he was repaired, Zero appears and utilizes the anti-Virus created by Doppler to erase Sigma for the time being. If Zero did end up critically wounded, including the method by which X receives the Z-Saber, Doppler uses the anti-Virus and sacrifices himself to destroy Sigma's programming.

Mega Man Xtreme 2
In Mega Man Xtreme 2, Sigma appears in Extreme Mode after the defeat of the Soul Erasers Berkana or Gareth, depending on if the player is X or Zero, where it's revealed he was behind the Erasure incident. In a rare instance, he's pleased that X defeated Berkana, claiming she went too far in her greed.


 * Sigma's first form is the same from Mega Man X2, "Neo Sigma", but his second form is new. The color of his second form is initially orange, but later alternates between blue and red, which can only be damaged by X while he is blue, and by Zero when red. His weak point is the big lion-like face in his chest.

Mega Man X4
Sigma was thought to be suppressed forever after Zero distributed the anti-virus created by Doppler, but he still manages to return. In the introduction of the game, Sigma, assuming a Grim Reaper-like appearance, acts as a double-agent between the Mavericks and Repliforce, a benevolent squadron of Reploids who assist the Maverick Hunters. Sigma's true motive is to conspire against Repliforce and turn it into a rogue enemy. He stages the bombing of the airborne metropolis Sky Lagoon, which plummets to the ground in the opening of the game.

With in-fighting between the Hunters and Repliforce threatening to destroy them both, Sigma increases his influence over the paranoid General of Repliforce. The General, an outspoken advocate of Reploid independence, loses all faith in peace and prepares a satellite laser attack on all humans, which is Sigma's real intention. Fortunately, Mega Man X storms the space weapon and stops the General before he can turn its sights on Earth. In the end, Sigma is revealed as the true mastermind and battles X himself, armed with a new body and a scythe. Despite his defeat at X's hands, he succeeds in part by destroying Repliforce.


 * If the game is played with Zero, Sigma reveals a portion of Zero's past involving their first encounter that possibly made Sigma a Maverick.


 * Interestingly, this is the only game where all of Sigma's audio pre-battle quotes are threats (eg, "Tremble with terror! YOU ARE FINISHED!", "Prepare to become space dust!", or "Are you ready for your final journey?!"). Also, despite being the final boss, his attack patterns in this game are simpler than some of the other bosses.


 * Another interesting fact is that Sigma's reasons for General, as well as all of Repliforce, to rebel is that humanity and the Maverick Hunters as well, seem to want to destroy anything that isn't fully compliant. Foreshadowing Dr. Weil's conception, as the latter gives a similar description of humanity.
 * Sigma's grim reaper form is the only time in any X series game were you cannot progress without using a special weapon; simply because it can only be damaged by X's Rising Fire or Zero's Ryuenjin.

Mega Man X5
It is some time before Sigma surfaces again. During his absence, Sigma traced Zero's origins to Dr. Wily, and hatches a plot to unlock Zero's "true" power — the Zero Virus — inside him. Sigma also adapts his programming to completely overwhelm the anti-Virus; the Sigma Virus quickly begins spreading everywhere, turning peaceful machines and Maverick Hunters alike into violent servants of Sigma. The Maverick leader also enlists the help of a Reploid bounty hunter named Dynamo to crash the orbiting space colony Eurasia into the Earth, as well as to hinder the Hunters' plans of stopping the collision.

Sigma's ultimate goal is to mix his own viral code, which is spread across Earth, with the original Zero Virus, and become all-powerful. Sigma hesitates to kill Zero, intending to make him "remember" who he is and revert back to evil. He fails in this endeavor, and both X and Zero defeat Sigma's new "Final Sigma W" body (which has been possibly powered and/or developed by Dr. Wily, although this may just be speculation) and "Gamma Sigma's" giant robot form (which stands several stories high). In the aftermath of the battle, Zero's severed torso lies dormant on the floor. X picks Zero up and tries to get him to respond. The remains of Sigma's head lying nearby suddenly become active and fire an energy laser directly at X and Zero, catching both of them in the chest. As Zero's body falls from X's grasp, he manages to fire one last blast from his Z-Buster and finishes Sigma. X is critically wounded in the battle, both from the battle itself and Sigma's final attack (the force of the laser being so strong that it ripped through his body and destroyed his entire lower half and arms), but he is eventually repaired by Dr. Light and returned to the Hunters.

Mega Man X6
Three weeks pass as the human population moves underground to survive the devastation and pollution left by Sigma's last attack. Sigma himself is quickly resurrected by a renegade Reploid scientist, Gate, who is angry at the scientific community for rejecting his advanced Reploid designs. He becomes a Maverick after coming into contact with a piece of rubble that contains signatures of the Zero Virus. Gate then uncovers Sigma's remains, and proceeds to rebuild him. However, due to the stress of spreading the Sigma Virus during Mega Man X5's "Colony Incident", Sigma's programming is damaged beyond what Gate can repair, and he is reduced to a half-conscious and barely-functioning wreck of his former self. Gate's work on Sigma's new body is unfinished by the time X confronts him at the end of the game. Although it seems as though Gate rebuilt Sigma merely as a backup plan to further his own goals, Sigma is quick to finish him off after X and Zero finally defeat Gate in battle, stating "Oh please, I did not die, nor did I need your help. Now get lost!". This is the only instance in Mega Man X6 that Sigma speaks coherently. He seems to remember little more than his rage toward X and Zero, and speaks in a garbled voice.


 * While the player only fights this "Reborn" form of Sigma in Mega Man X6, a similar looking one appears in the ending cinematic for Mega Man X7, as well as various cutscenes with Sigma and Red (this implies that Sigma may have been stuck in a worn down version of his body thanks to Gate).

Mega Man X7
Sigma reappears yet again, under the alias of "The Professor", to manipulate the hunting organization known as Red Alert. His plan is to use a mysterious young Reploid named Axl to copy the D.N.A. signatures of X and Zero and implant them into destructive war machines. The plan fails when Axl flees Red Alert and seeks asylum with the Maverick Hunters.

After being defeated, Sigma (who appears in a similar to his first form in Mega Man X6) punches Axl through a wall before vowing to X and Zero to again return in a new body.

Red, who had been defeated earlier and presumably killed, reappears, and Sigma attempts to possess him. Red is then revealed to be Axl, taking on Red's form, who then proceeds to blast Sigma out of a window.

Mega Man X8
Sigma's next plot was very complex, and it wasn't even him behind the entire scheme. It turned out that Axl was a prototype for a new generation of Reploids. These next generation Reploids possessed advanced copy abilities, and Alia discovered that the copy chips bore copies of Sigma's program among other powerful Reploids. Sigma instigated a new Maverick revolt with these new Reploids as the humans were evacuating Earth in hopes of finding a new home on the Moon. However, the revolt was stopped, Sigma was completely devastated, and the real mastermind, Lumine, the manager of the Jakob Project, was revealed and beaten. Before his death, Lumine made a startling claim: according to Lumine, Sigma was destroyed for good and not returning. It is believed that the reason Sigma would not regenerate within another body after his final defeat is that he was on the Moon, where due to the lack of available bodies to possess, the virus might have weakened in the vastness of space and got completely deleted (although he was also defeated in space in Mega Man X4, however, that time it was on a large battle weapon, not on the Moon; and the fact that Sigma didn't seem frustrated about this defeat implying that he could escape). There was also a lack of spare bodies, and his last body was hardly finished. However, his DNA is included in every copy chip of all the next generation Reploids so, technically, all new generation Reploids are infected with the Sigma Virus, and possibly Lumine too. It is unknown if Lumine's claims are true, although his absence in Mega Man X: Command Mission, as well as the entire Mega Man Zero (aside from a drama track in Mega Man Zero 3 detailing Elpizo's origins, and the Mother Elf's position supposed to be a "Sigma Antibody Program", which implies that Sigma may have survived until at least the beginning of the Elf Wars) and ZX series so far would suggest that he is not coming back, thus being X8 Sigma's last appearance.

Appearance
Though, Sigma has taken many drastically diverse forms throughout the X series, his humanoid design remains fairly consistent. He appears as a tall, intimidating humanoid Reploid and being one of the few in the series to go on without a helmet or headpiece of the sort, showing off his bald cranium. His facial features suggest the appearance of a middle-aged man, with a large square chin and small, blue eyes, and a small red jewel embedded in his forehead. His face also features a pair of scar-like marks run down both eyes, resembling a snake bite. How he got these scars vary: either from his first scuffle with a Maverick Zero, depicted in a animate flashback in Mega Man X4, where he was severely damaged (although it's possible Docter Cain repaired his fake skin after this) or as shown in The Day of Σ, where X in a fit of rage, burned the scars into Sigma's face with his bare hand (and may have shown the scars on his robotic skull from the inside). No matter what form he takes, Sigma always retains his head's initial appearance, making him easily recognizable.

Personality
Sigma was originally an honorable and selfless leader of the Maverick Hunters, but after his corruption became a power-hungry tyrant. He typically looks down on others and does not hesitate to kill the weak, laughing maniacally at their expense. Following his defeat, his further descent into madness transcended death, trying to hold onto any grip in the living world, in any form possible, consumed by the lingering thought of killing X. Amidst his madness, Sigma is a calculating and intelligent individual, and on more than one occasion, turned allies of X and Zero against them, and instigated many of the most destructive events of the Maverick Wars, including the Earth Crisis. Sigma is obsessed with Reploid evolution and superioty, and believes humanity has run it's course. Despite his hatred for X and Zero, Sigma once believed they were the future of all Reploids, and would lead them all into a new age.

Abilities
As the former leader of the Maverick Hunters, Sigma is a capable military leader, rendering him a devious and strategic opponent. When he turned Maverick, Sigma remains a charismatic leader, and is revived on many occasions by Reploid and Maverick admirers alike. Due to the Wily Virus in his circuits, he can survive seemingly anything and always return for more. He is a very powerful Reploid, and is fond of incorporating himself into battle suits which are vastly larger and more powerful than his "regular" form. Sigma is also a skilled manipulator, managing to turn various Reploids, Maverick Hunters, and Mavericks to his side. In fact, there were few instances in the entire series where Sigma wasn't pulling the strings. Sigma himself is one of the strongest Reploids ever created, due to his original role as leader of the Maverick Hunters.

Other media

 * Though not a starring character, Sigma was referred to in an episode of the 1994 Mega Man cartoon, where X, Vile and Spark Mandrill go back in time. His profile, shown by X, mistakenly spells his name as Cigma. The only line Sigma has is when Vile contacts him near the end of the episode — a short praise: "Well done, Vile".


 * Sigma also appears in a short unlockable OVA in the game Mega Man Maverick Hunter X for the PSP entitled "The Day of Σ". It shows the Maverick Hunters prior to the events of the game under Sigma's command, before he ultimately revolts. It should be noted that the events in this OVA coincide more with the canon of Mega Man Maverick Hunter X than with that of the original game.


 * In the Rockman X manga, Sigma starts the rebellion by killing a Maverick Hunter, Kyle, that was against him, and convincing various Hunters to join him by saying that Reploids are superior to humans and they should no longer take orders from them. When Spark Mandrill was giving up the fight against X with fear and saying he would tell all of Sigma's plans to him, Sigma uses a giant hologram of himself (via a flying mechanism) to kill Spark Mandrill. Before the fight against Armored Armadillo, it's shown that Sigma made a scar on Armadillo's left eye because he didn't follow his orders to defeat X in the forest. After defeating the eight Mavericks, Sigma appears and challenges X.

When X Encounters Copy Sigma (at Gateway)
X: Sigma!?

Copy Sigma: I shall allow you to call me by that name, for I am indeed Sigma.

X: You plan to take revenge on every Reploid... Every human... In the entire world? You're completely mad! I'm putting a stop to this right now!

Copy Sigma: Put a stop to what? We already control the moon. That old world has decayed and rotted. I will usher in a new world to replace it! But, before that, X, perhaps it's time for our final showdown!

When Zero Encounters Copy Sigma (at Gateway)
Zero: Sigma!? Can't say I was looking forward to seeing you again.

Copy Sigma: Zero. What a shame... You had the abilities and potential to become like me.

Zero: You... you tried to use my DNA. I'll teach you what happens when you mess with me!

Copy Sigma: I'm afraid not. The moon is under my control and the plan is entering its final stage. The moment of the world's unraveling is upon us!

When Axl Encounters Copy Sigma (at Gateway)
Axl: Sigma!? Did you think you could keep us away by running and hiding in space like a coward?

Copy Sigma: Run? Hide? You're mistaken. We merely chose to leave that ignorant planet behind.

Axl: Whatever you say. Either way, I'm gonna toast you right now!

Copy Sigma: Which one of us will be "toasted"? Let us see... You are not one of the chosen. Only we new Reploids may live in this new world! I've no use for flimsy prototypes!

When X Encounters the Real Sigma (at Sigma Palace)
Sigma: Welcome, Maverick Hunter. It's good to see you again, X. Our meeting was fated, X. Our destinies come to a head right here, right now. The time has come to usher in a new age. And you, X, are an essential part of it.

X: .........

Sigma: Your dedication to what you refer to as "justice" is what first got me thinking... I realized the imperfection of this world, and decided I must change it.

X: Don't blame me for your insanity, Sigma!

Sigma: Ha ha ha... It's too late, X. The gears are in motion. There's no turning back now. My children were the ones, X. The new generation Reploids were the ones. My children are responsible for the development of space. Mankind's lifeline...

X: Children!? What are you talking about?

Sigma: The Jakob Project... The program that gave birth to the new generation Reploids... It was all my doing! The world that was birthed by that plan rightfully belongs to me! Now, X... You will be destroyed along with the rest of this decayed world!

When Zero Encounters the Real Sigma (at Sigma Palace)
Sigma: Zero... Who could have imagined that we'd cross paths at the end of the world. The moment your virus entered my system, the seed had been planted. That's when it all began... The destruction of the world!

Zero: I've heard about enough of this garbage, Sigma.

Sigma: Don't get angry, Zero. I'm actually indebted to you. It is because of you that my children are able to create this magnificent new world in space.

Zero: Children? .........

Sigma: That's right. The new generation Reploids born of the Jakob Project all bear copy chips containing my personal data. Now, the end of the world, and of you, has come! Farewell!

When Axl Encounters the Real Sigma (at Sigma Palace)
Sigma: Hmpf. So you must be the one they call Axl... The prototype of the new Reploids. I'm surprised you've made it this far.

Axl: Hey... Stop calling me a prototype. I'm me. And you... You're a Maverick.

Sigma: You are a puny and weak prototype! Nothing more! Your copy ability is far from developed. That's why you were left out.

Axl: The Mavericks are one club I'd prefer to be left out of!

Sigma: Only the pure new generation Reploids - my children - are worthy!

Axl: Your children?

Sigma: Yes, prototype... My children. The new generation Reploids born of the Jakob Project all bear copy chips containing my personal data. And now, the final phase of that project begins! You shall be destroyed!

Trivia

 * Sigma (Σ) is the 18th letter of the Greek alphabet, and is used in mathematics to denote series, finite or infinite sums of variables. The Σ symbol is often seen on Mavericks from Sigma's army. Interesting, the Sigma (Σ) letter was originated from the Phoenician letter Sheen (W), which similar to the English letter "W".


 * There are three versions of the way Sigma got the scars on his eyes:
 * 1) Zero damaged Sigma's face when they fought (as shown in X4).
 * 2) X damaged his face in The Day of Σ (although he could have repaired the previous damage done by Zero). Ironically, after Sigma's head merges with the wolf robot in the game, his face resembles his face deformity received against Maverick Zero.
 * 3) Sigma did it himself after going Maverick in the manga, by using the heat of the "weapon" (his fingers) he used to shoot Kyle to make the scars.


 * Sigma is called Cigma in the Mega Man cartoon series.


 * According to Keiji Inafune, Mega Man's creator, Sigma's appearance was largely inspired by Doc Robot from Mega Man 3, one of the few antagonists in the series not designed by Inafune himself. He also stated that although Mega Man 3 is not a favorite of his from the original series' titles, Sigma is the only creation of his or any of his staff to borrow from that game's wealth of characters.

Sigma battle from Mega Man X
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