Durple belongs to Sprunki, the fan made Incredibox inspired music game where bright cartoon characters turn into horror versions in darker phases. As fans created more phases beyond the original transformation, each character gained increasingly distorted designs and sounds, and Phase 6 became shorthand for one of the later, more extreme stages. Clips of these phases spread through YouTube, TikTok and gaming edits, where viewers compare forms and rank their favourites. The Phase 6 cue stays popular because it signals that escalation instantly, even outside a full Sprunki video.