One of the least-used special abilities of dwarves is their 75% chance to determine new construction. When you read back over the history of the early Castle Greyhawk as run by Gary Gygax, we are told it was constantly in flux; new areas were being created, old areas were being re-worked, etc.
This is certainly not something that I’ve paid much attention to in the past myself, but it’s something I’ve included (via the Greyhawk Construction Company) but hardly emphasized in my recent Castle of the Mad Archmage work. But I think it’s an important piece of the megadungeon puzzle, as I’ve discussed in the past. They’re not static things; they are always in motion. Not just with creatures moving into new digs to replace ones that have been slain and traps being reset, but the very physicality of the place undergoing change. The pace can be slow, or it can be swift, but in order to capture the true notion of the megadungeon as a constant work-in-progress, it should not be ignored.
Interesting. I too have never paid much attention to that. I remember, in the early days, we cleared out a dungeon and turned it into our base of operations. One of the players drew up some renovations to the dungeon. That is the only time I recall having any interaction with "new construction" in a dungeon.
Sad that this feature of the game was lost along the way, part of the whole end-game jettisoning.
Imagine an ancient dungeon wall where someone put in a secret door, or where they renovated to fit their needs. Maybe they've been there for decades and are as much a part of a static dungeon as the rest of it, but they are more recent.
I see more use of the Dwarf's ability in detecting those things, in games I've played. Typically a DM will draw up a dungeon and then never change where the walls are.
Then again a lovely way to do it would be to block out certain squares as "wall or not wall" if you wanted a constantly-shifting dungeon layout. It would just alter pathways through the dungeon, but that alone may be enough.
A better way to lay out a shifting dungeon might be just writing the rooms and hallways down and then cutting them out, so they can be rearranged in any order. More Roguelike I suppose.
But that's a special kind of dungeon. What to do about denizens changing the walls and doors around on a quarterly basis? How to make that simple for a DM to track and manage?