Mega Man X is the first installment in the X sub-series, a direct spin off from the hit Mega Man series developed by Capcom. This game was originally released for the SNES gaming system in 1993 and later on the PC around 1995. The game presents an alternate Mega Man universe with new characters, story line, and game features that became a standard for later games of the series. Some of these features included faster and more intense game play, wall jumping, dashing, finding hidden items and upgrades, and bosses which cannot be defeated. While those differences made the game a hit, it did maintain the core elements that identify it as a Mega Man game: stage selection with 8 bosses to choose from, special abilities gained after defeating a boss whose ability is a weakness for another, and a final series of stages to that lead to a large boss battle, all with similar level designs and platforming. Overall, the game was received well and considered a success as it managed to introduce new ideas into an already established gaming architype.
The plot of Mega Man X, and subsequent games, revolves around the highly advanced prototype artificial robot life form known as X. In the year 21XX, an archaeologist by the name of Dr. Cain stumbled upon the buried laboratory of a legendary robotics designer known as Dr. Thomas Light. In the ruins Dr. Cain discovered a large capsule containing a robot advanced beyond anything in the world to date. The robot, Mega Man X, possessed independent human-level thought and emotion. Enthralled by his discovery, Dr. Cain and Mega Man X used Dr. Light's design to later produce the first "Reploid", a robot that can think, learn, feel, and grow like a human. This design took off and eventually became mass-produced, flooding the world with reploids.
However, as these stories go, the free will and independent actions given to the reploids eventually led some of them to turn on society. These robots became known as Mavericks and eventually the need for a police force to respond and control such robots became necessary. Thus, Dr. Cain the government established the Maverick Hunters, and elite, militarized repolid unit whose role was to capture and subdue any maverick robots that posed a threat to the people or society. To lead the the Hunters, Dr. Cain designed a special robot with an advanced intelligence system that was supposed to be immune to the causes of Maverick behavior; this robot was named Sigma. Unfortunately, over time Sigma himself became a Maverick and, with several of the hunters going with him, captured an island established himself the ruler and declared genocidal war on humans, now seeing them as inferior to reploids. Of the original Maverick hunters, only a mysteriously powerful robot known as Zero remained. Together, Zero, Dr. Cain, and X join forces to try and stop Sigma and his goals.