So I just had this happen: What other silly or awesome things have you had happen in Dungeons of Dredmor recently?
That room is one of Roguish Renovations, Interior Dredmorating, or FAXPAX. I do not recall which one though.
Don't do it! That Diggle has eggs back at the nest! If you end this Diggle, his young will never learn to fly.
I now have the great urge to subscribe to this mod, which is amazing as I'm pretty much a strictly vanilla (and official expansions) guy.
Roguish Renovations, Interior Dredmorating, and FAXPAX may as well be official expansions. I would bet no less than 3/4 of the people using these forums use them every character. *Edit* As mining says below, I omitted another mod that may as well be considered an official expansion. The Compleat Essential Skills Interior Dredmorating version 1.2.6.2 Roguish Renovation FAXPAX: A Thing What Fax Made These mods may as well be called "Unofficial Expansions". If you intend to play vanilla to avoid buggy mods, then stick with these. You will be very happy that you did.