Sigma (Mega Man X)

Sigma (Japanese: シグマ, Hepburn: Shiguma) is the main antagonist of the Mega Man X video game series. Created by Dr. Cain, Sigma was considered the finest of the Reploids and was the first leader of the Maverick Hunters, peace-keeping androids who defend humans against their renegade counterparts. Although he was once honorable, Sigma unexpectedly goes berserk during Mega Man X and rebels against humankind after coming into contact with the Maverick Virus. He defects to the Mavericks and assumes the role of their leader. Due to the virus integrated in his circuits, he can survive seemingly anything, and constantly returns to menace the world.

Mega Man X character
Mega Man X Sigma.png
Concept art of Sigma as he appears in Mega Man X
First appearanceMega Man X (1993)
Last appearanceMarvel vs. Capcom Infinite (2017)
Created byKeiji Inafune
Voiced byJapanese
In-universe information
AliasCommander Sigma
WeaponBeam saber

Sigma has appeared in almost every Mega Man X video game since his first appearance in the 1993 title Mega Man X. He has received praise from critics and fans for his design and charisma as a villain, though his introduction was noted as marking a darker and more pessimistic theme for Mega Man X compared to other Mega Man sub-series.


Sigma appears as a tall, bald humanoid in most of his forms. As the former leader of the Maverick Hunters, Sigma is a capable military leader, rendering him a devious and strategic opponent to his primary enemies, X and Zero. Sigma is a skilled and charismatic manipulator, managing to turn various Reploids, Maverick Hunters, and Mavericks to his side. Although he has been destroyed countless times, Sigma's programming always survives, either building himself a new form,[1] or is revived by Reploid and Maverick admirers alike; it is implied that he grows more insane with each revival. He is fond of incorporating himself into battlesuits which are vastly larger than his "regular" form. He serves as the final boss in all games except Mega Man X: Command Mission and Mega Man X8 (he does not appear in the former and in the latter, Sigma is the penultimate boss).


Mega Man X seriesEdit

Prior to the first Mega Man X game, Sigma was the most advanced Reploid of his time, leading the Maverick Hunters. However, one day, the Maverick Hunters received reports of an overwhelmingly powerful "Red Maverick" that destroyed an entire squadron of Hunters (the Gamma unit). While investigating, Sigma, along with his unit, tracked it down to an abandoned laboratory, and faced Zero alone. Zero, an evil robot created by Dr. Wily that carried the Maverick Virus, inadvertently transferred the virus into Sigma before being defeated. The virus adapts to Sigma, becoming the Sigma Virus.

After gradually succumbing to the virus, he suddenly leads a mass revolt among the Reploids, declaring total war on humans.[2] Many Maverick Hunters follow Sigma out of loyalty, leaving Zero in charge of the organization. By this time, he has reformed and become a powerful Maverick Hunter. X, the last creation of Dr. Light and the base model for every Reploid, decides to volunteer and joins Zero. 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.[3]

Sigma returns in each installment of the series in various forms, but is defeated by X each time. His last appearance is in Mega Man X8 - after he is finally destroyed for good, the Sigma Virus remains, prompting the events of the Mega Man Zero series.

Other gamesEdit

Sigma is given a crossover with the robotic villain Ultron in Marvel vs. Capcom Infinite, as the two are merged into Ultron Sigma and serve as the game's primary antagonist.[4] Sigma as a playable character is available for purchase as standalone downloadable content or as part of the game's character pass.[5]

Cartoons and animeEdit

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 lines Sigma has is when Vile contacts him near the end of the episode.

He also appears in a short unlockable OVA in Mega Man Maverick Hunter X entitled "The Day of Sigma". It shows the Maverick Hunters prior to the events of first Mega Man X game under Sigma's command, before he ultimately revolts.


Mega Man X was originally meant to have a team of three villains, one tall, one short, and one chubby. However, the designs by Keiji Inafune were merged to create the single villain, Sigma. These designs were later reused as the basis for Mega Man X2's X-Hunters.[6]


A figure of Sigma was released by Tamashii Nations in 2013.[7]


Sigma was praised for his backstory, resulting in the story of Mega Man X having unclear morality. Peter Tieryas of Kotaku stated that he felt guilty after defeating Sigma, due to the Mavericks' origins as normal Reploids whose design was patterned after the series protagonist, and that they just wanted independence.[8] Heather Alexandra of the same publication noted the character's heavy similarities with Overwatch's Sigma, to the point that they could be the same character. She called the Mega Man Sigma "a bit of a pest, to say the least" due to his ability to "leap into new robot bodies and other computer systems".[9]

Patrick Lee of The A.V. Club, however, stated that Sigma is "exactly the sort of boogeyman anti-progress allegories are built around". Saying that he is the "first piece of technology the Mega Man series suggests was a mistake to create", he says that Sigma runs contrary to the previous, optimistic themes of the series, which suggest that technology is ultimately beneficial to mankind, and that robots are "morally neutral tools".[10] He described this "more cynical worldview" as "anti-technology scaremongering."[10] With regards to Sigma's appearance in Marvel vs Capcom: Infinite, Mike Fahey from Kotaku thought the merging of Ultron and Sigma into an amalgamated being is "a great idea, and makes for a very cool visual", although he felt the game's idea of characters from Capcom's Mega Man, Resident Evil and Street Fighter franchises sharing the same world and knowing each other to be silly.[11]


  1. ^ Mega Man Homepage - X Characters. Retrieved on 2006-8-6.
  2. ^ MMHP: Mega Man X. Retrieved on 2006-8-6.
  3. ^ Sigma: You have won a temporary victory, X! What you destroyed was only a temporary body -- my spirit remains intact. In time I will find bodies strong enough to do my bidding and I will return. I will see you soon, X. Very soon... Capcom Mega Man X (in English) 1993-12-20 (US)
  4. ^ "E3 2017: Marvel vs. Capcom Infinite Has Infinite Potential". Hardcore Gamer. 2017-06-14. Retrieved 2020-10-19.
  5. ^ Nathan Birch (November 1, 2017). "Marvel vs. Capcom: Infinite Trailer Unleashes DLC Fighters Black Panther and Sigma". WCCF Tech. Retrieved 2020-10-19.
  6. ^ Mega Man X Official Complete Works. UDON Entertainment Corp. 2009. p. 93.
  7. ^ "This Mega Man X Sigma figure is absolutely amazing". Destructoid. Retrieved 2020-10-19.
  8. ^ Tieryas, Peter. "The Brutal Lessons Gaming Taught Me About Revolutions, Robots, And War". Kotaku. Retrieved 2020-10-19.
  9. ^ "Sigma vs. Sigma: The Comparison We Had To Make". Kotaku. Retrieved 2020-10-19.
  10. ^ a b Lee, Patrick. "Playing God: The ever-changing morals of Mega Man's sci-fi allegory". The A.V. Club. Retrieved 2020-10-19.
  11. ^ Mike Fahey. "Marvel vs. Capcom: Infinite's Story Demo Feels Like Awkward Fanfiction". Kotaku. Retrieved 2020-10-21.