[TOMT] Creepy, weird, crude animation on Youtube

I'm requesting a name/URL/creator's name for this weird and creepy animation I saw a rather long time ago on youtube, maybe 10 years ago. My memories regarding it are somewhat vague and I might remember something incorrectly, but I'm sure anyone familiar with the animation will recognize it based on my description. It started with some really weird dude riding a really weird horse in a really weird environment with a really weird and scary atmosphere. Every now and then the horse gave out an ear wrenching, completely un-horse-like shriek. I remember this horse rider arriving to a building of some kind. Inside this building there was another really weird character, running back and forth along a wall. I recall they had some kind of a fight at some point, I'm not really sure. I don't really remember anything more about the plot. I think the animation was at least partly 3D and it certainly wasn't made by any professional studio, just some user on Youtube.

It might be that this animation had just a couple views on Youtube and virtually no one knows of it so this TOMT might be a reeeally long shot. But I'll give it a try. :D