Overlord began as a light novel series by Kugane Maruyama before Madhouse adapted it into an anime in 2015. Its opening themes, performed by the duo OxT, mix heavy rock with orchestral and choral elements to match the story of a player turned undead ruler. Clips of the openings spread through anime edits, AMVs and gaming montages on YouTube and TikTok, where the dramatic intros now signal an unstoppable villain entrance.