Sigma

Character Info
	Artwork from Mega Man X.
Appearances
General information
Name(s):	Sigma
Appearances:	Mega Man Games:; Mega Man X, Mega Man X2, Mega Man X3, Mega Man X4, Mega Man Xtreme, Mega Man X5, Mega Man Xtreme 2, Mega Man X6, Mega Man X7, Mega Man X: Command Mission, Mega Man X8, Mega Man Maverick Hunter X, Mega Man X DiVE Other Games:; Marvel vs. Capcom: Infinite Other Media:; 1994 animated series, Archie Comics
1994 animated series info
Voice:	Jim Byrnes
Episode(s):	Mega X
	v; t; e;

Sigma is a main character in the X era and the main antagonist in most X games. He is a highly advanced reploid originally built by Dr. Cain to lead the Maverick Hunters, but becomes infected with the Maverick Virus himself after battling Zero, driving him to despise humanity and become a threat to the world. The virus later fuses with his programming into the Sigma Virus, a form in which he survives throughout the series even as his bodies are destroyed.

Though Sigma uses many different bodies and forms throughout the games, most are recognisable by incorporating his bald, robotic head into their design in some capacity.

In the Games

Mega Man X

Sprite of Sigma with his cloak, from Mega Man X.

Sigma debuts in the first Mega Man X. According to the manual, he was built by Dr. Cain prior to the events of the game to lead the fight against Mavericks, reploids that have gone haywire and are posing a danger to humans. Though Sigma was built with special protections, he goes Maverick himself and takes most of the other Hunters with him, prompting X to take up the fight together with Zero, the new leader of the Maverick Hunters.

X does not encounter Sigma until Sigma Stage 4, at the end of the game, though the entirety of his fortress uses his portrait as the map picture on the stage select screen. After X climbs to the top of a vertical shaft, Sigma teleports in, wearing a cloak, and gloats that he could easily destroy X, but will leave him to his pet wolf, Velguarder. If X succeeds in defeating the wolf, Sigma returns, observing that X is "almost as good a hunter as [he] was", then throws off his cloak and engages X with his original battle body, armed with a beam sabre.

When Sigma is defeated in this form, his body is destroyed and only his head remains, which floats up onto a giant wolf-like robot in the background and continues to fight as Wolf Sigma. When X is once again victorious and the robot begins to explode, Sigma insists that he cannot be destroyed by X and questions why X is fighting against reploids, claiming that he could have "ushered in a new age" if he had been allowed to destroy humanity.

Although defeated, Sigma appears again on a computer screen after the credits roll, revealing that X only succeeded in destroying a temporary body and his "spirit" remains intact, likely referring to the Sigma Virus. Sigma states that he will find other bodies and threatens to return "very soon", a threat he follows up on in the next game.