1. Executive Summary Stage Mugen refers to user-created fighting arenas designed for the free, highly customizable 2D fighting game engine MUGEN (created by Elecbyte). Unlike stages in commercial fighting games, Mugen stages are not limited to a single game's aesthetic or mechanics. They can feature interactive elements, complex animations, dynamic scaling, parallax scrolling, custom music, and even scripted effects. This report outlines the structure, features, creation pipeline, and community ecosystem of Mugen stages. 2. Technical Architecture of a Mugen Stage A standard Mugen stage is defined by a .def (definition) file and associated image/sound assets. Key components include: