It makes the building seem VERY scary. Ponies go in, Changelings come out. No pony can warn the others because no one knows about, they don't know about it because no one returns as they were before they entered.
What a gorgeous design! I always love seeing original works of art, and the architecture alone in this piece is lovely. Nice scenery, too. The colours remind me of the art style in the show Gravity Falls for whatever reason- maybe the warm brown with the forest green? I don't know. That's my reaction, anyway. I just wanted to say it's cool