Jevil is a secret boss in Chapter 1 of Deltarune, Toby Fox's role-playing game released in 2018 as a follow-up to Undertale. Players find him locked in a prison cell beneath Card Kingdom, and defeating him is one of the chapter's hardest optional challenges. Short clips from his battle, including this transformation sound, spread through fan edits, soundboards and meme videos because they instantly signal chaos and escalation. It remains popular with Deltarune fans who recognise Jevil's manic laugh and unpredictable attacks, even in a clip lasting barely a second and a half.