User blog comment:JAlbor/Dishonored AMA with Harvey Smith/@comment-1500935-20151214203358

I didn't know we had all the transcript of an AMA post-release with both lead developers. I haven't read it all in detail, but that bit is interesting:

Question: What was the most obscure idea that got rejected from being in the game?

Answer: ''Hm, Raf and I just consulted across the room on this one... Probably the power where you could become a shadow, 2-dimensional, and slide along walls.''

From what we see in the trailer of Dishonored 2, it seems like they kept some part of that idea. Well obviously not the paper thin form idea.