Users can modify reality via the creation of "mods", customized fragments of reality overwriting the original. Each modification must be precisely defined in order to work properly, the last ones overwriting the previous in case of contradiction. These mods can do almost anything, add new elements, remove existing ones and modify any aspect of reality. Each of them can be activated and deactivated at will, re-modified or removed, allowing users to try out an unlimited number of experiences without consequences.