The NetBook of Dungeon Keeper Rules

From the introduction:

As many of you know there have been thousands of dungeons that have been destroyed by those wretched heroes and other hazards. Heroes come and go and destroy everything in their path. Many have found the dungeon a difficult task, others will have nightmares to remember and still others will be lying in eternal sleep as a puddle of blood on the dungeon floor.

Heroes have spoken of the "final enemy", as they put it, who is the mastermind of it all. Sages have finally named these masterminds as Dungeon Keepers.