"Street Fighter X Mega Man is a crossover platform game created by Singaporean fan developer Seo Zong Hui with support from Capcom. The game will be free to download from Capcom-Unity on December 17, 2012. The game celebrates the 25th anniversary of Capcom's Mega Man and Street Fighter franchises, mimicking the design of classic Mega Man games but with Street Fighter characters substituting as important enemies encountered in the game.
The game mimics the appearance and gameplay style of Mega Man games released on the Nintendo Entertainment System, and Mega Man uses the same set of moves (the slide and the charge shot) featured in Mega Man 4. Rather than using wholly original stages and Robot Masters, the stages share influences with stages from the Street Fighter franchise and characters such as Blanka, Chun-Li, and Ryu take the place of the Robot Masters as the end of level bosses. The Street Fighter characters use their signature moves as attacks; in addition, they have their own Super Meters that build up when they take damage during the boss fights and allow them to launch a powerful attack at Mega Man once filled. Like other Mega Man games, defeating each boss earns Mega Man a new weapon based on the characters; in this game, Mega Man earns famous Street Fighter attacks such as Ryu's Hadouken and Chun-Li's Hyakuretsu Kyaku."
Source: Wikipedia, "Street Fighter X Mega Man", available under the CC-BY-SA License.