OSR: Imperial Megapalace - Rapid Dungeon Assembly

On Saturday, Feb. 1st, the Pirate group TPK'd to beetles (and greed).
On Sunday, I despaired at the need to find a new genre, system, or plan. The Pirate game, after two TPKs and many hijinks, had run its course.
On Monday, I decided to write a Byzantine megadungeon.

Next game is scheduled for Feb. 16th. If you're in that game, look away! Spoilers abound.

Here's either how I wrote a megadungeon in two weeks.... or how I failed miserably.
 

Step 1: Concept Map

I picked an approximate layout. A round fortress-palace with four towers and a central dome. Crypts and a cistern underneath.

Then, I started tossing rooms onto a piece of paper. I went through existing palace maps (real and fictional) to find common rooms. Adjacent sections overlap or are placed nearby.

Ideas started to solidify. The dungeon would initially have one entrance, but more could be found and opened. Each tower would be guarded by a classic mythical beast. The dungeon will be a testbed for the Monster Overhaul, full of creatures and reskins for convenient playtesting.
 

Step 2: Draft Map

I decided to map the dungeon in Sketchup. It's not an ideal mapping tool, but it does have some handy features:
-ease of rotation
-components (items that can be cloned, but editing one item edits them all)
-ease of checking sightlines and overlap of complex regions

Starting with the south tower and working outwards, I started mapping rooms and zones. I didn't worry about assigning specific functions or occupants to every room. That can come later.

I did start planning routes. Assuming the players enter from the south, where can they go? What will bottleneck them? Is the dungeon sufficiently jaquayed?

I imagined a party moving through the dungeon. What would they see? Where would they go? What about the dungeon's original inhabitants? How would they use this space? Would an Emperor share a corridor with servants? What would diplomats see?

Mapping the dungeon will be a challenge. I'll probably provide players with template maps or approximate scribbings, or let them map it pointcrawl-style.
 

Step 3: Stocking Maps

Main Level

Upper Level + Towers

Crypts

The map is very heavily jaquayed. Some sections are linear or gated, but the bulk of the dungeon is criss-crossed with multiple paths, weird loops, and interesting choices. Secret doors are often one-sided (one side is hidden, one side is obviously a door). If approached from one side, they can create a shortcut back to a previously explored area.

The clock tower (the north tower) has two rotating sections. The bottom section rotates as players discover keys or gears. The upper section rotates on a 1 hour timer.

I want a mix of small and large rooms. Fights should require manuvering and flanking. Give players space to stretch out. Engulf them in the majesty of the Last Emperor.

At this point, the maps are ready to be stocked. They are still drafts. As I stock them, I'll remove and edit rooms, make notes, and scrawl corrections. 
 

Step 4: Stocking Subsections

I like minimaps. They make running complex dungeons much easier.

I am currently cutting the main map into sections. 3 are present in the image above: the South Tower, the Hippodrome, and the Menagerie.

Numbers are assigned based on probable routes players will take. To minimize flipping, each section will have its own half page, whole page, or 2-page spread.

I'm also writing very brief room notes as I assign numbers. No evocative prose, no details, just "gate" or "manticore" or "trap." If I have details I add them, but at this stage it's better to get the content down. I can always punch up the prose after playtesting.

This section takes ages, especially if I have to renumber a section or find I've missed a critical room. Splitting the dungeon into subsections helps.
 

Next Steps

Stock, stock, and stock some more.

If you've got ideas for things that lurk in the Imperial Megapalace, let me know in the comments. I can't guarantee I'll take your suggestion (or any suggestions), but it can't hurt to throw ideas out there. Procopius might help.

I'm not sure if this dungeon will become a free product, a Patreon exclusive PDF, a paid Kickstarted thing, or something else entirely. It depends on how the playtest goes, how much I like the final product... and if I get it finished in time.

Scratchpad Notes

To Do

-d100 Encounter Table
-I Search the Body
-d50 / d100 table of backgrounds (not using -lings this time).
-review these tables (good work, past Skerples) and use them.
 

Inhabitants

The Last Emperor
-Anyone who eats his flesh becomes sort-of immortal.
-Also cursed. A lot.
-Regenerates, but is weak.
-Built an Artificial Hell under the palace to torment enemies. Also serves as a regeneration point if he is killed.
 
Medusa
-With blind tigers.
-Possible to negotiate with but far easier to avoid.
 
Manticore
-Lazy
-Probably the first "big" monster the PCs will meet.
-Guards a path up to the Royal Prison.
 
Twisted Giant
-In the cathedral. A bishop grown large. Wields a censer.
 
Ogres
-Twins. One in the Prison Below, one in the Prison Above.
 
Harpies
-In the west tower. Pick off creatures who scale the walls.
 
Hereditary Eunuchs
-Don't ask.
 
Ketolysis Monks
-Flame breath from ketogenic starvation.