Mods, short for modifications, are user-created changes to a game's code or assets that alter or add new content. In the case of Mitsurugi Kamui Hikae, mods can range from simple tweaks to gameplay mechanics to entirely new storylines, characters, and stages. These modifications are typically created by fans using various tools and software, such as game editors or modding frameworks.
Because the game was built on a proprietary engine, you won't find expansive gameplay overhauls like those for Devil May Cry mitsurugi kamui hikae mods