Ultra M is an EXE adapted by Marco Antonio, and is the main antagonist encountered in Mario's Madness. The character itself is a take and draws inspiration from Shadow-Shana's "Super Horror Mario", and is based directly on a piece of art made by the aforementioned user.

As of Mario's Madness V2, his lore was updated, providing additional context and connection to the character and the Friday Night Funkin' Continuity. This can be found by pausing in his songs, Its-a-me, Starman Slaughter, and All-Stars.