If you are searching for an "Xtreme" version, you are likely looking for a modified ISO that enhances the gameplay beyond the standard release.
Downloading the file is only half the battle. To truly experience the "Xtreme" quality of the game, you must run it on the (PC/Android) or a modded Wii.
: Updates player stats and move charge times to provide a more competitive and balanced experience compared to the original.