Sigma's Bodies

Sigma has used a plethora of bodies throughout the Mega Man X series. After his original body was destroyed during the events of the first game, Sigma returned in a new form. He is able to return again and again due to the power of the Sigma Virus that he is bonded to.

Sigma usually appears as a bulky, bald humanoid in most of his first stages; 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.

Mega Man X
This is the body Dr. Cain originally built for Sigma before the events of the first game. Sigma's first body was designed with a beam saber; in fact, contrary to popular belief, it was Sigma who was the first to use one in the series, and not Zero.



Mega Man X2
Just as he said he would, Sigma returns and assumes leadership of his Maverick forces. He gains a new robot 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 in capturing and re-assembling the remains of Zero, whom he plans to reprogram to kill X in the final battle of the game. Because X managed to recapture all of the remains of Zero from the X-Hunters, he was forced to make a copy of Zero's body that was not unlike Zero's Black Zero form, but it ended up being completely destroyed by Zero before it could battle X. Sigma then mentions that he "knows Zero's secret", and that he's destined to serve him, but Zero says he still would have taken Sigma down anyways, causing him to say that he'll love dismantling Zero. It's unknown what exactly this secret Sigma says, but the dialogue suggests that it has something to do with his being created by Dr. Wily, and possibly the origin of the Maverick Virus as Sigma calls him "the last of the Doctor's creations". Sigma attacks in a new form, armed with clawed hands, but X thwarts his plans and destroys him again. This marks the first time Sigma's viral form is seen, as the Final Boss as the game. Zero is then restored to his rightful place in the Maverick Hunters, and given his own command as leader of Special 0 Unit.



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 the revolts 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 he is defeated 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 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.



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.



Mega Man X6
Three weeks pass as the human population moved 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.



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 D.N.A. signatures of X and Zero, then 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 form 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 and presumably killed, reappears, and Sigma tries to possess him. Red is revealed to be Axl having taken on Red's form, and then blasts Sigma out of a window.



Mega Man X8
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. The revolt was stopped, Sigma was completely devastated, and the real mastermind, Lumine, the manager of the 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). There also was a lack of Sigma's 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.

