Super Mario Bros. Z is a fan-made sprite-animation web series created by Mark Haynes, better known as Alvin Earthworm, which debuted on Newgrounds in 2006 and became a cult hit by fusing Mario and Sonic lore with anime-style battles. Mecha Sonic, its cold machine villain, grew into a fan favorite whose threats circulate online the same way lines like the enemy spotted callout do. Though the series was never officially finished, later reboots and fan edits kept Mecha Sonic's menace alive in memes and versus videos.