Here's a scan of a dungeon I drew in about 30 minutes using the template I posted the other night. I came up with an evil boss who was a duergar artificer building a "dark iron golem" into which he planned to transfer his spirit before going forth to wreak havoc on the surface world. His bane is the imaginatively named "iron-bane wand" which can corrode the magical ore his slaves are digging up to smelt into the metal he needs to make the golem. I think it was left there as a fail-safe by the goodly gnomes who first discovered the ore.
I plan to run this as a one- or two- shot Dungeonteller adventure for kids and parents. I'll let you know how it went.