Megalovania is the fast, intense battle theme associated with Sans in Undertale, the role-playing game released in 2015, and it became widely recognised through gameplay videos, remixes and covers. The intensifies format grew online as a way to signal that a situation was escalating, and guitar versions gave the theme an even harder, rock-style edge. Linked here to DanTDM, a long-running Minecraft creator, the clip works as shorthand for a moment turning serious, which is why editors still reach for it for reveals, challenges and mock boss fights.