Metal Sonic first appeared in Sonic CD in 1993 as a robotic double built to outrun Sonic, while Ryomen Sukuna is the ancient King of Curses from Gege Akutami's Jujutsu Kaisen, which began as a manga in 2018. The pairing itself comes from fan versus culture online, where characters from completely different universes are matched by power, speed and aura. Short clips built around impossible fights spread easily on TikTok, YouTube Shorts and Discord because viewers instantly understand the joke and start arguing about who would actually win.