Markiplier is the online name of Mark Fischbach, an American YouTuber best known for horror game playthroughs and energetic, expressive reactions recorded during long gaming sessions. Short exclamations from those videos are frequently clipped by fans and shared as standalone reaction sounds. This holy crap line became a compact shorthand for shock online, reused in edits, streams and meme compilations where a familiar creator voice says what the audience is thinking. Its brevity and clear delivery have kept it in rotation long after the original moment.