This viral ad for X-Men: Apocalypse is an inspired piece of marketing. It appears as a warped VHS recording of "In the Footsteps Of..." a fictional supernatural TV documentary program, in the style of real ones like In Search Of--which I used to watch with rapt elation/horror/wonder as a kid. Heck, they even got George Takei as a stand-in narrator, a la Leonard Nimoy.
This one gives a glimpse to the background of the new film's main big-bad, Apocalypse himself, En Sabah Nur.
Advertising can be a lot of fun, when cleverly done!