Creating a megadungeon – The laboratory layer

Previous post

In the previous post (which granted was quite a bit ago) about my (yet another) attempt to create a megadungeon, I have rougly outlined the reasoning as to why the megadungeon even exists in the first place, as well as the three layer structure of it – the layers that require to be properly fleshed out.

Here, I am starting with the laboratory layer, which is middle layer. I find it to be the most crucial to the overall structure of the dungeon – and there are the two reasons for this. The first one is the lore of this dungeon I have decided upon, and the second is the fact that since it is in the middle, it affects the other two layers. If I started with either the upper or the lower layer, each of them would only have a significiant impact on the middle layer's structure.

The basic logic

The mere existence of this laboratory layer immediately poses two significiant questions. The first one, is why is it so deep underground, and the second is how did that wizard get down there in a reasonable amount of time. Thankfully, both of these questions can be easily answered.

The question of why the laboratory would be so deep underground, can be simply explained due to the danger and percieved value of the magical rock. Requiring someone to go into a somewhat deep underground to even have a chance at stealing the results of a wizard's work is more than enough to persuade many potential thieves to look for a different target – and if something goes wrong, the distance between the laboratory and the surface should be more than enough to not cause too much trouble.

The answer for the second question is similarily simple – a long tube leading down underground. If you have played Terraria, think something in vein of a hellevator. The mage would just cast a spell that would let them safely descend or ascend through it, such as Levitate – a level 2 spell in B/X D&D. Sure, a mere existence of such a hole is definitely an OSHA violation, but let's be honest – the underground laboratory dealing with dangerous magical rocks is a massive hazard in itself, the pit of death is a small deal in practice.

It should be easy to notice that from the gameplay standpoint this hole is a very visible – and arguably very accessible method of fast travel. And yet, the question might be, whether or not it is too accessible. Even without spells, a determined group of first level adventurers may attempt to get down to the bottom of this well by climbing down using ropes. It is arguably both a concern from the gameplay standpoint and the lore standpoint, but in practice, I can't imagine players speedrunning to their demise like this... and even if they do, it should go without saying that the wizard did invest in some defense mechanisms. A level one party might be able to topple one golem, two if they are lucky – but they will simply have no resources to reasonably explore a fifth or sixth level of the dungeon. And well, if they go in without any plan to get out, then let's be honest, they deserve to lose their characters. No amount of GM fiat should be able to get them out of such a situation – situation created by their own sheer stupidity. And you can't even claim that the danger was not telegraphed – even if they are completely new to dungeon crawling, and don't know the simple fact that the deeper you go, the more dangerous it is, the mere idea of risking having no way to get back to the surface should give you enough warning to stay out if you are not ready.

Such fast travel method might be also difficult for other GMs to prepare, as they would have to get at least basic familarity with several floors at once – floors that are large and have multiple factions of importance each. The thing is, I do not consider publishing this megadungeon as a campaign module to run at other tables – this is supposed to be a megadungeon for my own use as a GM. And sure, I do not reject the possibility of publishing this thing – but it is not a priority of mine in the slightest.

Magical rocks

To make sense of the laboratory, it would be reasonable to know the properties of these magical rocks. When thinking of these rocks, I had in mind something akin to radioactive rocks, like uranium or plutonium – but I do believe reproducing their effects one to one would be somewhat undesirable and possibly a bit boring.

So, here are the properties of this rock:

Well, that's quite a bit – but there is no reason to expect players to leave such rocks be. The players will definitely try to experiment with these rocks, provided they will find them in the first place. Not only this, listing properties like this makes fleshing out the laboratory much easier – and it will allow for some cool writing to be done.

Architectural fun

As we finally know how this magical rock functions, it will be much easier to figure out how the lab should look – or at least what it should contain.

Let's start with the structure that should be the most impressive. Since we are talking about a thinly veiled radioactivity reference, why not put a massive reactor in a huge room that vertically spans two floors of the dungeon? The exact details o how it works and how it looks can be done later, but it should be a good idea to add a nearby source of water for cooling purposes – something like an underground river should work fine, and can provide another three dimensional structure in form of an underground ravine.

As the danger of the magical rock is significiant, and the mage will be nowhere to be found, most of it will be hidden within a hidden vault. I've yet to determine how exactly the vault will be hidden, but it will definitely be something that most parties won't be able to just find.

Summary

To summarize all the key points of this layer I want to include: * A large shaft leading to this layer * Reactor spanning two dungeon floors * Underground river