Abc123.mp4

: When played, the file features several text-to-speech (TTS) voices from FL Studio that deliver a direct warning to the listener. It essentially tells the data miner that there are no secrets here and asks them not to post everything they find online, as it ruins the mystery for others.

In the original game files for Undertale , developer Toby Fox included a sound file titled to catch "data miners"—players who dig through code to find secrets before they are meant to be seen.

: The file became so iconic that it was later used in an Alternate Reality Game (ARG) by YouTuber Sr Pelo for his Underpants parody series. Technical and Educational Context abc123.mp4

The "abc123.mp4" file name is often a placeholder used in technical documentation, but it is also a well-known reference in the Undertale community to a hidden file named . The Story of abc_123_a

: It is frequently used in technical documentation, such as the Pruna P-Video guides , to demonstrate how to iterate on video generation prompts using draft modes. : When played, the file features several text-to-speech

: Numerous YouTube channels like Jolly ABC TV and brands like Scholastic Early Learners use "ABC 123" branding for videos and workbooks designed to teach toddlers basic literacy and numeracy.

Outside of gaming, "abc123" is a standard placeholder string used in various fields: : The file became so iconic that it

: Despite the message claiming there are no secrets, the eerie, robotic tone of the voices led many fans to associate it with the game's most mysterious character, W.D. Gaster .