No mercy

The joke first appeared on the video, Bonetruosle - Undertale, released on Jan, 1, 2019. the joke originates from the song No mercy by the living tombstone. here is a list of it's appearances.
 * Bonetruosle - Undertale
 * World of light - Super smash bros Ultimate
 * (YTP) Hotel Trans-Reevania 3
 * A certain Someone's Memories - MOTHER 3