I.K.E.M.E.N began development in 2010 by SuperSuehiro on the now-archived Google Code service, using a proprietary programming language called S-SIZE, also created by Suehiro.
Because of its open source nature, the engine has been split into multiple versions handled by different individuals the original I.K.E.M.E.N was created by SuperSuehiro, which was later forked and extended into I.K.E.M.E.N Plus by K4thos, and later rewritten in the GO language as I.K.E.M.E.N GO by SuperSuehiro, which is currently maintained by multiple individuals. Unlike M.U.G.E.N, the engine is open source, which allows users to modify the engine outside of simple content additions, as well as the addition of new features, such as new state controllers and menus. The engine is notable for introducing stage zoom prior to the release of the M.U.G.E.N 1.1 beta, and for allowing netplay matches, a feature that is not supported in any official build of M.U.G.E.N.
I.K.E.M.E.N (short for Itsumademo Kanseishinai Eienni Mikansei ENgine) is a free and open-source fighting game engine designed to be compatible with M.U.G.E.N content, while also expanding on its feature set to allow for more flexible customization.
