Zero rises again in Capcom’s latest release, Mega Man Zero/ZX Legacy Collection on Switch, PlayStation 4, Xbox One and Steam. While Mega Man is a retro gaming icon, Zero rose to fame himself throughout the Mega Man X series. Today, he is almost as recognized as the Blue Bomber himself among retro fans.

Zero's story is long and intertwined with Mega Man X. For fans who aren’t familiar with Zero’s past but want to know more about this sidekick turned hero, this is a good place to start.

Related: The Mega Man Zero Series Is Better Than Most of the Franchise

Origins

Zero is one of the few tie-ins to the original Mega Man games. He was never in them, but the game alludes to his creation by Dr. Wily -- not Dr. Light like Mega Man. He was meant to surpass Mega Man, but Wily was unable to control him due to a flaw in his system and chose to seal him in a capsule instead.

Years later, after Wily’s death, Zero was found and released by a group of Reploids, whom he subsequently destroyed as he was still malfunctioning. Eventually, this news hit the Maverick Hunters, who then tracked down Zero. Zero destroyed a Unit and was confronted by Sigma. Originally, Sigma was a Maverick Hunter Commander and not the final boss fans know from the X series, although this was the decisive battle that would change that.

Sigma nearly lost until Zero’s helmet gem flashed a W, and he was momentarily weakened. Sigma took the chance to strike and broke the gem, defeating Zero. It was around this time Sigma became infected with the Maverick Virus. Zero’s body was recovered by the Maverick Hunters and brought to Dr. Cain. After recovering and showing no more signs of the Maverick Virus, Zero became part of the Maverick Hunters.

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Zero and X met in the same Maverick Hunter company, and the two became friends while serving under Sigma during a time of particularly bad Maverick incidents. During the investigation, Zero uncovered Sigma’s betrayal and learned he was infected with the Maverick Virus. This is where the first Mega Man X game begins.

The Early Games

In 1994, Mega Man X hit the West on the SNES. After players lost a fixed fight against the game’s intro stage boss, Vile, they heard the sound of a Buster charging up. Vile is nearly blown away and retreats as a Maverick Hunter in red arrives to save X. That Hunter was Zero, making his debut for Western audiences. Later in the game, players would fight Vile in his ride armor a second time. Just when it looked like the duo would be defeated, Zero sacrificed himself to destroy the ride armor giving X a fighting chance. At this point, not much was known about Zero besides that he was X’s partner.

In Mega Man X2, players learn that three Mavericks called the X-Hunter’s obtained Zero’s Parts, which are required to rebuild him. This is a sub-quest within the main game where, by finding and defeating bosses, X could gather the parts. Canonically, this does occur, and Dr. Cain rebuilds Zero. Later in the game, Zero, once again, assists X as his sidekick.

Related: These Mega Man Games Need the Zero/ZX Legacy Collection Treatment

Mega Man X3 begins with X and Zero crashing a robot into a facility, clearly fighting together. After discussing the routes they'll take to suppress the Mavericks, Zero leaves, and the game begins as normal with the player able to control X. However, halfway through the stage, X is captured by a Maverick Hunter gone rogue, and Zero comes crashing through the ceiling.

This was the first-time players got to actually play as Zero. It was exciting, as he not only had a powered-up Buster, but also a lightsaber follow-up after shooting. Players got to use Zero to save X before continuing the rest of the level as normal. After completing the intro stage, players could call on Zero to play as him with some exceptions. He couldn’t fight bosses, and if he died, became unplayable. Still, it was exciting for fans, as up until then, he only showed up to help X.

The PlayStation Era

Zero really came into his own in the PlayStation series of Mega Man games. This was the first time he could be chosen to playthrough the game instead of X. Players got to use his saber rather than a Buster, and he learned different techniques after defeating bosses, which acted like combos. His playstyle is closer to the way the Zero in Mega Man Zero/ZX functions. Plus, during this time, Zero’s plot became deeper.

Mega Man X4 starts with a reoccurring dream where Zero’s creator (obviously Wily by the outline) tells him to obey and destroy his enemy. The player is sent to the intro stage, where they encounter a faction called Repliforce, and an all-out war breaks out between them and the Hunters. By the end of the game, Zero finds himself wondering about the fate of Reploids and Mavericks -- a crucial part of Zero’s story in the next game.

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Mega Man X5's story focuses on Zero and circles back to his origins. The Maverick Virus breaks out on the space colony Eurasia, which is set to hit Earth. Meanwhile, the Hunters have to deal with an outbreak of their own, as the Sigma Virus is turning many in their rank Maverick. However, it has a different effect on Zero, since he was exposed to the original Maverick Virus while in the capsule in Wily’s Lab.

Zero is able to stop Eurasia and survive, but debris rains onto Earth, causing the Maverick and Sigma Viruses to merge and become the Zero Virus.

Though Zero shows no symptoms, his infection increases the closer he gets to the source of the new virus. Out of concern for his friend, X steps in and tries to get Zero to return to the Hunter Base. After refusing, the two long time friends battle each other for the first time, which ends in a draw. Sigma then steps in to attempt to destroy them both, but Zero stops him and Sigma retreats.

If the player is using Zero during the final battle, Sigma reveals that he crashed the colony to corrupt Zero and revert him to his violent self. He tells Zero he met an Old Man who took care of him and infected him with the Maverick Virus to awaken him, possibly alluding to Wily and explaining why Sigma became infected from their first battle. Sigma attempts to finish off X, but Zero, once again, sacrifices himself to destroy Sigma.

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Originally, this was meant to be the true ending of the X series and where Mega Man Zero would begin, but Keiji Inafune (the creator and designer of Zero) had to change his plans when another game was made. Mega Man X6 continues where X5 left off with a crazed Reploid scientist finding a piece of Zero. He uses it to create a virus version of Zero called Zero Nightmare. Since Zero is dead, the player must play as X, who eventually defeats the virus. X learns that Zero wasn't actually dead, just in hiding to repair. X and Zero are reunited, and the next two games see Zero return as a playable character.

Which Brings Us to Mega Man Zero/ZX

After gaining popularity through the Mega Man X series, Zero returned in 2002 with a series of his own: Mega Man Zero. This game marked the first time Zero was on his own. While playing through the new Mega Man Zero/ZX Legacy Collection, fans will find some interesting character dynamics (new and old) and plot twists along the way.

Over the course of the franchise, Zero became an iconic character in his own right, something few others have achieved. From an unseen character in the original games, to a supporting character in the Mega Man X series, and, finally, to his own series, this character truly has gone from Zero to Hero.

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