Fido is a Veteran Chinese Mugen creator originally from the Mugenchina forums community before it shut down.
He was also known as FidoMX, and lifido9999. He was very active on most of the main Mugen forums such as Mugen Fighters Guild and MugenFreeforall. He is famous for creating over 40 characters from the Street Fighter Alpha and SF3 series in his own original custom gameplay groove mechanic style callled SF MX, MX or MMX (Street Fighter Megamix/Mugen Megamix). He was the most active between 2008 and 2014, but he was active in Mugen since as early as 2004, possibly earlier.