According to planner Sho Tsuge & designer Kazunori Tazaki, before the game's title, Mega Man X, was chosen, it was first named Super Rockman as a working title.
The intro segment of the boss theme is very similar to the stage select screen theme from Mega Man 2.
The Homing Torpedo weapon is misspelled as "Horming Torpedo." This was fixed in Mega Man Maverick Hunter X.
On the U.S. box art for both the PC and SNES versions, Launch Octopus can be seen with a purple color instead of his red color seen in the game.
If you use the boomerang cutter when fighting Flame Mammoth you can cut off his trunk so he can't shoot the oil slicks.
By viewing the demo then putting in a certain password to trigger a bug where you start at Central Highway but with all Heart Tanks, Sub-Tanks, Weapons, and all the Mavericks defeated, once you complete the intro stage you can go straight to Sigma's Fortress.
The enemy Batton was an enemy that appeared in several classic Mega Man games, starting with Mega Man 2. In Armored Armadillo's stage, a single Batton can be found among the Batton Bones, the X series replacement for the Battons. Chronologically speaking (and excusing the enemies abilities to respawn when off-screen), this could be the last accounted Batton in the Mega Man universe.
In Megaman X, it is possible to learn the "Hadoken", Ryu's signature move from the Street Fighter series. After beating the game, obtain every Sub Tank, Life Up and Armor Parts. Then play through Armored Armadillo's stage until the last rolling platform. As the platform bursts out of the tunnel and through the sky, dash-jump off of the platform and ascend the wall right on top of the gate to Armored Armadillo. There you will find Dr. Light wearing a Karate uniform. He teaches X the technique.
Originally, Zero was a redesign of the Mega Man character as portrayed by the lead artist, Keiji Inafune. However, Zero looked too different from the original Mega Man so, fearing a negative reaction from fans, Inafune gave him a new name and a secondary role to the new Mega Man X, who was then designed to be more similar to the original Mega Man.