Megalovania originally comes from Toby Fox's Undertale, released in 2015, where it plays during the Sans boss fight and became one of gaming's most remixed tracks. Fans constantly rebuild it in other tools, and Chrome Music Lab's Song Maker, part of Google's Chrome Experiments for music education, made that easy with shareable links. Clips like this one spread as lists of Song Maker versions, with creators swapping links and challenging each other to recreate famous game melodies in the simple browser sequencer.