This page contains a comprehensive list of the different file types used by the M.U.G.E.N engine and any additional content such as characters, stages and screenpacks. Please note that extensions for text-based files can be substituted with any other extension, as M.U.G.E.N is able to read any extension as long as there's unformatted text inside the file; as such, some creators may choose to not use the default extensions at all, with the exception of the .def file, which has to remain as such.