Inafune created the character Zero, whom he originally intended to be the game's main, playable protagonist. "When the "X" series came out, I really wanted to redesign Mega Man," Inafune explained. "I wanted a totally different Mega Man. I’m a designer, a creator; I wanted something new. I didn’t want to use the same old Mega Man." Fearing a negative reaction from fans, Zero was ultimately reduced to a role secondary to Mega Man X. The development team additionally wanted the world of "Mega Man X" to be much more sophisticated than in the first "Mega Man" series. They wanted to accomplish this with Zero's "hardcore" personality and the game's antagonist Sigma. As stated by Inafune, the original series' villain Dr. Wily had "a side to him you couldn't really hate". Sigma, however, was written as a once-good character suffering an "unforeseen error" that leads him to be completely evil. The game's story went through several changes during development. Two allies of Mega Man X, named RX and RY, appeared in previews for the game, but were later taken out. "Mega Man X" altered the franchise tradition of having themed boss characters with a "Man" moniker by replacing them with anthropomorphic animal-like androids. The art and pixelization for these eight bosses were divided among three illustrators: Inafune did Storm Eagle and Chill Penguin; Kaji did Spark Mandrill, Launch Octopus, and Sting Chameleon; and Kazunori Tazaki (credited as Ikki) did Flame Mammoth, Armored Armadillo, and Boomer Kuwanger. The team was careful in making the bosses distinct from one another in both stature and coloring. Tatsuya Yoshikawa (credited as Tatsunoko), a fourth artist who had recently been hired by Capcom, was given the task of assisting the rest of the team by designing, illustrating, and creating the sprites for the game's minor enemies.