Developed in conjunction with Street Fighter fan Seow Zong Hui of Singapore, the game was originally pitched to Capcom at EVO 2012. The game will also feature an 8-bit style, soundtrack by A_Rival, mixing classic Mega Man tunes with chiptune interpretations of the Street Fighter character themes.

Given the popularity of Mega Man 9 and Mega Man 10 it shouldn’t be a huge surprise to see the Mega Man franchise continue in its retro-styled form, but both the Street Fighter crossover and the fact that it is a free game are both unexpected twists. There are no current plans to bring Street Fighter X Mega Man to PSN or XBLA, so if you want to play, plan on hooking up a gamepad to your PC.

“Our fans have been so supportive of the 25th Anniversary efforts on Street Fighter, that we wanted to provide one last surprise and token of our appreciation,” said Christian Svensson, SVP of Consumer Software at Capcom USA. “This game symbolizes the passion and dedication of our fans and with the 25th Anniversary of Mega Man coming up, we felt it was our duty to bring this wonderful experience to everyone who has shared the last 25 years with us and both of these celebrated franchises.”

Street Fighter X Mega Man will be available as a free download, direct from Capcom on December 17, 2012.