This sound comes from MapleStory, the side-scrolling online RPG first released in the early 2000s. The level up cue became memorable because players heard it constantly while grinding, questing and improving their characters. Outside the game, creators adopted it as a quick shorthand for progress and achievement, especially in gaming clips and glow-up style edits. It still stays popular because the sound is short, upbeat and instantly understandable even without visuals from MapleStory itself.