876874076983263232 Mp4 -

If your query is about the format itself, is a multimedia container used to store:

The search results indicate that you are likely referring to a technical discovery within the fan community where players can replace the feature.mp4 file (specifically associated with the "feature presentation" screen) to customize the game's visuals. Undertale Feature Presentation Modding

In the context of Undertale , particularly on PC versions, the game uses MP4 files for certain scripted sequences.