M.U.G.E.N. is a customizable 2D fighting game engine that allows users to create and play fighting games with characters, stages, and lifebars of their own design. The term refers to the process of acquiring character files, which are generally compressed archives containing the necessary sprites, audio, and configuration files, and integrating them into the M.U.G.E.N. engine. For instance, a user might locate and obtain character files representing iconic fighting game figures, such as Ryu or Kyo Kusanagi, to add them to their personal M.U.G.E.N. build.
Acquiring character files extends the functionality and replayability of the base M.U.G.E.N. engine significantly. It enables players to curate a roster of fighters spanning multiple franchises and art styles, fostering unique and often unpredictable matchups. The availability of these files dates back to the engine’s widespread adoption in the late 1990s and early 2000s, with a vast community contributing to and sharing character creations across various online forums and repositories. This collaborative spirit has resulted in a near-limitless array of playable characters and stages.