MUGEN 1.1 was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. We recommend checking the downloaded files with any free antivirus. This free tool was originally created by DB Ultimate Mugen 2007 v2. The most popular version among MUGEN users is 1.0. The program's installer file is commonly found as mugen.exe. MUGEN relates to Games.
From the developer:
M.U.G.E.N is a 2D fighting game engine that is enables you to create commercial-quality fighting games. Almost everything can be customized, from individual characters to stages, as well as the look and feel of the game.
The majority of content created for M.U.G.E.N tends to be distributed as individual characters, stages or motifs. Assembling a game is as simple as downloading the content of your choice, and configuring M.U.G.E.
You may want to check out more software, such as Extra Mug Shot Sticker, Dragon Ball Z : Extreme Mugen or Create A Gift, which might be similar to MUGEN.