When you filter FMs by "most popular" and play some of them for a while, you get a feeling for different "guilds of builders". The people that helped DirkBogan make this cool mission are among the top creators for the thief community. No wonder the mission has some Into the Odd (claustrophobic spaces and books with only titles) and The Black Parade (maze like layouts) vibes, but it definitely also stands on its own. Yes the sight of the whole valley ascending into the sky via various stairs and doors is the crown jewel. But I also found that the ambience and overall atmosphere are just great! Do read the briefing document so the readable make more sense. The title ascend and the starting position at the bottom kind of push you to go up, but sometimes once up you have to come down from a different angle to access a new area.

I first completed this on Normal and when I went back to the starting area, like it said in the objective, nothing happened. I wondered around for a few, then started a new game on Expert and it starts you off in a different spot. Then it will make sense of what to do when you end the mission.