The Great Machines are the greatest artifices of the Lich Lords' art. They are gigantic machines of iron, wrought via brute force and the most delicate of magics. They are powered through manual labor, usually that of lesser undead servitors -- the "mindless undead", typically lesser skeletons, zombies, and ghouls. Because these creatures do have a tendency to forget the task at hand and begin mindlessly slaughtering everything around them, a fair amount of attention must be devoted towards keeping them at their task. But the undead do not need to be fed, and, importantly, they consume no water, so they are a crucial labor force, used not only on the Great Machines, but as workers in all industries requiring unskilled labor.

The Lich Lords' cities are most active when it is dark, since the undead, many of their masters, and many of the non-human races that comprise a significant percentage of the cities' population, are sensitive to the light. Most of these cities are partially underground or have extensive underground construction, as a result.