Deltarune is a role playing game created by Toby Fox, first released in 2018 as a companion to Undertale, known for its memorable chiptune inspired soundtrack and sudden shifts between humour and unease. Short musical cues from the game are widely clipped and shared by fans as reaction sounds. This creepy jingle spread through gaming edits and soundboards because its brief length makes it easy to drop into any video. It remains popular for signalling dread, parodying horror reveals and adding a familiar game reference that Deltarune players recognise instantly.