Dropping a City

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Kind of an odd question. Whats a 'believable' way to drop a city into a deep underground cavern without destroying it or killing the population. I say believable in the sense that we are talking about doing this in a world of magic and monsters. Still, I'd like to keep the use of magic in this situation to a minimum, rather than the somewhat cop-out explination of 'oh it was just a spell or ritual that did it'.
Kind of an odd question. Whats a 'believable' way to drop a city into a deep underground cavern without destroying it or killing the population. I say believable in the sense that we are talking about doing this in a world of magic and monsters. Still, I'd like to keep the use of magic in this situation to a minimum, rather than the somewhat cop-out explination of 'oh it was just a spell or ritual that did it'.

Ask your players, of course. If they think it's plausible, that's all you need.

Purple worms undermine the ground.
Ice/water archons/elementals crack and erode the ground, forming a sinkhole.
Beholders disintegrate the natural supporting pillars.
Greedy mining has degraded the land.

If I have to ask the GM for it, then I don't want it.

Hm, I suppose those are plausible reasons. However, I'd really like the cause to be more mysterious. The idea behind this is that the city fell into the earth a long time ago and was thought to be lost. I'm envisioning it being rediscovered, and being a very, dark, mysterious place now, full of intrigue and brimming with stranger new creatures. The setting will serve to introduce a somewhat Neo Victorian culture to my game world along with the psionic power source.
Hm, I suppose those are plausible reasons. However, I'd really like the cause to be more mysterious. The idea behind this is that the city fell into the earth a long time ago and was thought to be lost. I'm envisioning it being rediscovered, and being a very, dark, mysterious place now, full of intrigue and brimming with stranger new creatures. The setting will serve to introduce a somewhat Neo Victorian culture to my game world along with the psionic power source.

Jeez, man. Mysterious, but not magical. You don't half want much, as you move the goalposts. But it seems clear to me that the early Neo-Victorians, coming into their new psionic powers, sought to isolate themselves but didn't know how. One night, they all passed into a fainting sleep, during which their psionic powers were focused through their collective, repressed ids to push the town into the earth.

If I have to ask the GM for it, then I don't want it.

Kind of an odd question. Whats a 'believable' way to drop a city into a deep underground cavern without destroying it or killing the population. I say believable in the sense that we are talking about doing this in a world of magic and monsters. Still, I'd like to keep the use of magic in this situation to a minimum, rather than the somewhat cop-out explination of 'oh it was just a spell or ritual that did it'.




1.  The city was built deep underground. Titans, Dwarves, and Gargoyles are your friends here. Food and light could come from fungal culture. Phosphorous Mushrooms would be a primary light source.

2.  If you are worried about Oxygen, you should look up Termites and Ants on google. There is a unique type of ant/termites (both) that farm fungus underground, and build massive towers over their homes for air ventilation. Pretty neat, and if Real Life bugs can do it, so can Dwarves.

3.  The world is full of huge, massive caverns, some which don't even have access to the surface. All you need is a species "native" to the place. You can also take a clue from Archeology; many wonderful places are buried underground, deep underground. This can occur because when a place is abandoned, and geological events occur, layers grow over them - this can be from volcanic ash, accumulation of debris, earthquakes and landslides. Over time, another species might migrate into the area and discover it, then choose to inhabit it.

There is enough mystery about the "normal", and sometimes a ball is just a ball. Sometimes, I like to toss out mysteries, let players grapple with them, drop in a few factoids; then the players will begin rationalizing out the possible answers, and from your players ideas you can get the best material and give them a sense of achievement at the same time. (Holy Crap, I was right!)

www.goreme.com/derinkuyu-underground-cit...
www.ncbi.nlm.nih.gov/pubmed/11409051
www.pnas.org/content/99/23/14887.long

I hope these article inspire you.



Within; Without.

If it's supposed to have happened long ago, and it's supposed to be mysterious, DON'T explain it.  It happened, and people (probably including those who live there, who might have guesses as to what happened, but who knows if they're right) don't really know why.  That's the definition of a mystery.

Unless it's actually important to the plot, why explain it.  If it is actually important to the plot, then the way in which it is, should provide the explanation FOR you.  If a bad guy sank it, work out the most likely way he'd've done that, and that's how it happened.
Harrying your Prey, the Easy Way: A Hunter's Handbook - the first of what will hopefully be many CharOp efforts on my part. The Blinker - teleport everywhere. An Eladrin Knight/Eldritch Knight. CB != rules source.
Slow massive sinkhole that took generations...and its denizen built around it...
My thoughts:

Slow massive sinkhole that took generations...and its denizen built around it...


This if you want the 'non-magical' way to sink a city without damaging anything

But it seems clear to me that the early Neo-Victorians, coming into their new psionic powers, sought to isolate themselves but didn't know how. One night, they all passed into a fainting sleep, during which their psionic powers were focused through their collective, repressed ids to push the town into the earth.


This to encourage the focus on psionic magic & still have an undamaged city
The city never actually existed. It was always a psychic manifestation of people who were imprisoned underground. They were kept or kept themselves in a state of meditation, while their projected avatars moved about on the surface. Something happened to shock all the people out of their meditation, and now they have other concerns than maintaining the ersatz city. But they have done what they can to reproduce it underground.

If I have to ask the GM for it, then I don't want it.

Alien abduction:

One night, generations ago, the Derros turned on one of their great machines, and paralyzed the surface town. 

Then, the Derros crept up from their vaults below the earth, and abducted everyone from their beds, and took them screaming down into the caverns below, where special cleaners wiped most of their memories, and installed the people in an underground city prepared for the purpose.

Tales about open skies and sunlight and stars and fresh air are now just a legend among the terrified population. 

Cycled light and air circulation is provided by the Derros machines, humming constantly from hidden tunnels below.

On nights of the full moon in the surface world, the Derros come out hiding in their vaults of madness to conduct strange and disturbing experiments, breeding programs, treatments of life extension to keep their subjects alive long past their natural life spans, further abductions, and worse on the people of the city, turning off the lights, turning on their paralyzation rays, and creeping from house to house with their strange underworld servants and masters to haunt the people in their nightmares.

Upon awakening, nobody is quite sure what happened during the night, as their memories are fragmentary and feverish.  Strange religions, legends, and theories have been developed to explain away the Derros as gods, as products of overactive imaginations, as creatures of the night.  One of the chief religions of the city is a temple which claims that this is not reality, that everyone went to sleep one night and never woke up, and now exist in a sort of dream, where they are characters in a deranged game or play performed by the creatures of their nightmares.  Those who have faith may one day wake up from the nightmare, and return to a natural life in sunlight again.  Those who do not have faith, say the priests, will be doomed to sleep forever in a coma tormented by this nightmare simulation of life.  Even the highest priests of this religion do not know that their holiest book was written by the Derros, its holiest mysteries the deranged ravings of the insane, sadistic subterranean race.

Sources:


  • "E is for 'Elevator People'", a very short story from Harlan Ellison's "From A to Z in the Chocolate Alphabet"

  • Richard Sharpe Shaver's stories of the Deros (Wikipedia link)

  • the film Dark City (Wikipedia link)

[spoiler New DM Tips]
  • Trying to solve out-of-game problems (like cheating, bad attitudes, or poor sportsmanship) with in-game solutions will almost always result in failure, and will probably make matters worse.
  • Gun Safety Rule #5: Never point the gun at anything you don't intend to destroy. (Never introduce a character, PC, NPC, Villain, or fate of the world into even the possibility of a deadly combat or other dangerous situation, unless you are prepared to destroy it instantly and completely forever.)
  • Know your group's character sheets, and check them over carefully. You don't want surprises, but, more importantly, they are a gold mine of ideas!
  • "If it ain't broke, don't fix it." It's a problem if the players aren't having fun and it interferes with a DM's ability to run the game effectively; if it's not a problem, 'fixing' at best does little to help, and at worst causes problems that didn't exist before.
  • "Hulk Smash" characters are a bad match for open-ended exploration in crowds of civilians; get them out of civilization where they can break things and kill monsters in peace.
  • Success is not necessarily the same thing as killing an opponent. Failure is not necessarily the same thing as dying.
  • Failure is always an option. And it's a fine option, too, as long as failure is interesting, entertaining, and fun!
[/spoiler] The New DM's Group Horror in RPGs "This is exactly what the Leprechauns want you to believe!" - Merb101 "Broken or not, unbalanced or not, if something seems to be preventing the game from being enjoyable, something has to give: either that thing, or other aspects of the game, or your idea of what's enjoyable." - Centauri
In 4E there are several sunken cities. One was drug underground, literally, by a god who is himself imprisoned underground. (I'm blanking on the name of the city, but I believe it was Torog who destroyed/removed the city and it is detailed in the Underdark book).

Another city, Moil, was inhabited by demon worshippers who suddenly lost their taste for evil. As punishment for turning from him, Orcus, demon god of undeath, hurled the city into the Shadowfell and the people there slowly became hungry undeath as the dark swamp slowly began eating away at the city itself, sinking it into the black marsh.

Neither is "realistic," but both are terribly evocative and trigger a dozen storyhooks. That's what you want.

Oh, Gauntlegrym in Forgotten realms. An underground city, but I believe there are sunken cities surrounding it. Dwarven settlements that were buried when a vocano erupted.
In 4E there are several sunken cities.

fwiw: Lantan is FR's equivalent to Atlantis (complete with higher tech). It sunk as part of a cataclysm.

Moil

isn't underground, though.

In 4E there are several sunken cities.

fwiw: Lantan is FR's equivalent to Atlantis (complete with higher tech). It sunk as part of a cataclysm.

Moil

isn't underground, though.




Might as well be. And it is sinking. Still counts ;)
If it's supposed to have happened long ago, and it's supposed to be mysterious, DON'T explain it.  It happened, and people (probably including those who live there, who might have guesses as to what happened, but who knows if they're right) don't really know why.  That's the definition of a mystery.

Unless it's actually important to the plot, why explain it.



Agreed! I'd take it a step further and leave it blank for myself, too. The mystery will be revealed and explained as it makes sense in context during actual play. We'll all have the fun of seeing what the story is with this weird place, DM included.

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 I'd personally go with To Be Decided Later, as well.


 However, from a geological perspective, the most likely suspect is... Volcanos.

 If the city is located in an are that's volcanically active (and it doesn't need to be all Mount Doom obvious, either) it's perfectly possible for the land under the city to be sinking as the magma pool beneath it drains out into the surrounding area which continues to build up slowly until over millenia it forms a bubble over the city and eventually completely swallows it miles beneath the earth.

 Being volcanically active, there's a strong chance of seismic activity as well - and ye gods, who the hell knows what-or-who's causing the earthquakes and volcanos...

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All good advice. I appreciate the help.

I have a follow-up question. My intention is to base the majority of gameplay within this city. At least one tier of play, possibly two (10 -20 levels). This means the city will have to be big. I also envision this city as being mostly self contained, able to provide its on food, water, and resources with minimal exterior help. Also I'm hoping to include a few different environments besides just city streets. I'm wondering how large to make the city. I'm thinking it will be several miles across, but I'm not sure how many. It will have a major river running through it, along with a stretch of marshes along the bank.
All good advice. I appreciate the help.

I have a follow-up question. My intention is to base the majority of gameplay within this city. At least one tier of play, possibly two (10 -20 levels). This means the city will have to be big. I also envision this city as being mostly self contained, able to provide its on food, water, and resources with minimal exterior help. Also I'm hoping to include a few different environments besides just city streets. I'm wondering how large to make the city. I'm thinking it will be several miles across, but I'm not sure how many. It will have a major river running through it, along with a stretch of marshes along the bank.



My suggestion is only create specific areas as they are needed for the story. You can say what you pretty much just typed, use that as the basic description, then see where the players want to go, what areas you need to flesh out. Don't build the city up front (though I understand a lot of people enjoy that kind of creativity) but let it be developed through exploration.

Have maybe 3-5 named locations at the start of the game, like the lord's manor, the jail, the inn, the market area and the graveyard/pit of souls. Those don't need to be mapped, just be ready to create something if you need a fight or something tactical.
All good advice. I appreciate the help.

I have a follow-up question. My intention is to base the majority of gameplay within this city. At least one tier of play, possibly two (10 -20 levels). This means the city will have to be big. I also envision this city as being mostly self contained, able to provide its on food, water, and resources with minimal exterior help. Also I'm hoping to include a few different environments besides just city streets. I'm wondering how large to make the city. I'm thinking it will be several miles across, but I'm not sure how many. It will have a major river running through it, along with a stretch of marshes along the bank.



I saw this old blog post recently which may be of interest on this if you haven't read it before:

angrydm.com/2010/08/schrodinger-chekhov-... 
Kind of an odd question. Whats a 'believable' way to drop a city into a deep underground cavern without destroying it or killing the population. I say believable in the sense that we are talking about doing this in a world of magic and monsters. Still, I'd like to keep the use of magic in this situation to a minimum, rather than the somewhat cop-out explanation of 'oh it was just a spell or ritual that did it'.




Many Goblins with many barrels of alchemichal black powder.  Knock out the support struts holding up the city below the cellars and dungeons near the underdark.

Think natural columns formed in the deep underground, likely the subterranean levels near what would be the underdark.  All those natural support columns formed by stalagmites and stalactites forming together with barrels upon barrels of black powder tied all around them, and some Goblin ingenuity, and you have yourself a sunken city.
Wow that many tiers in this sunken underground cavern city setting... then my fello dm friend, you must make this setting feel like a world of its own. The feel and perception of the players is important. Perhaps like the true concept of middle earth... another world within earth, with the core of earth as the sun...some people believed this in the past, believing aurora was its light escaping from the grou d, reflecting on the sky..

I would make your setting feel massive enough to feel like a world setting, enough for pc to stick around till 20 lvl and not lose interest and decide to get out of the cavern sort to speak.
If you're aiming for RLish plausibility then there's a limit to how large the cavern could be. However, it doesn't need to be one cavern.

Also, consider this: there might not be much of the original city left, both because of the initial sinking and the inevitable wear and tear (much of which would be difficult to cope with in an underground environment - surface cities tend to use surface materials for construction and repair). There's still some of it left, but since then the inhabitants have had to adapt to their new surroundings.

As such, there might be an "Old City" core (though probably a pretty ramshackle looking one - perhaps even considered the bad part of town), with the rest of it having spread out into the surrounding rock, making use of other, existing tunnels, caverns, and structures that predated the city itself.

This also gives you an reason to have diverse city sections. The "Old Town" doesn't look much like the section that was once an abandoned dwarf-built monastery, and neither of them resemble the fungal caverns over yonder, etc.
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Back to Basics - A Guide to Basic Attacks You might be playing DnD wrong if... "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." Albert Einstein
 a massive world event moved literal mountains or earth and stone into a shell where the city once stood, kicking up so much sediment that the entire area was raised high enough to make the change hardly noticeable. The city just... vanished.
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Kind of an odd question. Whats a 'believable' way to drop a city into a deep underground cavern without destroying it or killing the population. I say believable in the sense that we are talking about doing this in a world of magic and monsters. Still, I'd like to keep the use of magic in this situation to a minimum, rather than the somewhat cop-out explination of 'oh it was just a spell or ritual that did it'.



Maybe it was a natural event that caused the city to drop/fall but powerful magics were uses to prevent its destruction, but now its trapped in the Underdark

"Poor Gandalf.  When the city started to fall, he used his most powerful magiks to throw a shield round the city.  But it drained the life out of him, and new we are stuck here with no way out."
Hm, I suppose those are plausible reasons. However, I'd really like the cause to be more mysterious. The idea behind this is that the city fell into the earth a long time ago and was thought to be lost. I'm envisioning it being rediscovered, and being a very, dark, mysterious place now, full of intrigue and brimming with stranger new creatures. The setting will serve to introduce a somewhat Neo Victorian culture to my game world along with the psionic power source.

It would be interesting to tie the cause into some secret way of life of the townsfolk, maybe some kind of twist on the mining angle.

Example: Perhaps they were digging up some kind of rare, scattered magical ore that had an unexpected effect when collected and concentrated within the city. This ore could be the thing that gave them psionic powers over the generations, but it's also slowly pulling the city toward the Underdark/Far Realm/Torog/some other bad thing. This would be a well-kept secret amongst the townfolk, maybe even only known to those with psionic powers.

A lot of the intrigue you want could be directly tied to whatever caused the city to sink. If it's something that benefits the citizens (or only some of the citizens) but also endangers the city, you could have factions based on that and allow the party to join one side or the other. Eventually as they learn the whole history of the city, their choices can effect whether it is eventually saved or destroyed.
Mysterious...  then make it obvious and eliminate all conventional way it ended up there.  The sprawling city and it's denizens were mysteriously teleported into the massive cavern long ago, (cause unknown even by it's denizens).  Ultimately, when the players eventually discover the truth... it was a terrible massive magical accident or even intentional, perpectuated by Consortium of Wizards.. the hidden political power behind the scene...a terrible secret they had been hiding for ages, so it's denizens never discover the truth.  To make it even more mysterious.. the denizens are mixtures of Planer Races, Shadowfel races... etc etc.  When reading about the history of the city in the archives...shows, initial denizens basically woke up one day and their city was in the cavern.

For reasons unknown, original denizen's blood line can't leave the city or it's massive underground cavern world, or they get sick and quickly die... so here they are making a life secluded in this world of theirs.  Perhaps the consortium made a secret deal with a god that went bad, and must hide the city from a god bent on revenge... so much possibilities.

Perhaps the epic adventure at 20th level for the pc's is not only to discover it's truth.. but somehow get the city back to it's original world, if that world still exists.

Mystery after mystery players can explore...Something along that line... you get the gest.
Figaro Castle in Final Fantasy VI.

Long ago, the castle could tunnel underground to escape sieges. One day, its engines broke and the people were stuck. The tunnels collapsed and the citizens are unable to repair the engines without help.

What were they running from?
Why did the engines stop working?

Those, your players can seek the answers to.

Within; Without.

The city crawls:  it is carved into the shell of a titanic burrowing mollusc, dissolving its way through the earth over the course of centuries as it seeks out the subterranean horrors it feeds upon.

The city's sages can usually "steer" the city by magic or by technology (pouring a cauldron of boiling lead down a pit in the shell to the creature's flesh ought to do the trick), but sometimes the creature the city is built in just goes dormant for reasons that are not always clear to the city's inhabitants, causing long periods of the city existing in a single location, punctuated by a sudden change as the creature begins moving again.

Inspiration:  Hieronymous Bosch's weird paintings of people walking around inside hellish living buildings (Bosch's paintings in general should be enough on their own to inspire several monster manuals....)

Edit to add:  Oh, yeah, and Pietr Bruegel had his fair share of monsters and living buildings, as well...
[spoiler New DM Tips]
  • Trying to solve out-of-game problems (like cheating, bad attitudes, or poor sportsmanship) with in-game solutions will almost always result in failure, and will probably make matters worse.
  • Gun Safety Rule #5: Never point the gun at anything you don't intend to destroy. (Never introduce a character, PC, NPC, Villain, or fate of the world into even the possibility of a deadly combat or other dangerous situation, unless you are prepared to destroy it instantly and completely forever.)
  • Know your group's character sheets, and check them over carefully. You don't want surprises, but, more importantly, they are a gold mine of ideas!
  • "If it ain't broke, don't fix it." It's a problem if the players aren't having fun and it interferes with a DM's ability to run the game effectively; if it's not a problem, 'fixing' at best does little to help, and at worst causes problems that didn't exist before.
  • "Hulk Smash" characters are a bad match for open-ended exploration in crowds of civilians; get them out of civilization where they can break things and kill monsters in peace.
  • Success is not necessarily the same thing as killing an opponent. Failure is not necessarily the same thing as dying.
  • Failure is always an option. And it's a fine option, too, as long as failure is interesting, entertaining, and fun!
[/spoiler] The New DM's Group Horror in RPGs "This is exactly what the Leprechauns want you to believe!" - Merb101 "Broken or not, unbalanced or not, if something seems to be preventing the game from being enjoyable, something has to give: either that thing, or other aspects of the game, or your idea of what's enjoyable." - Centauri
The city crawls:  it is carved into the shell of a titanic burrowing mollusc, dissolving its way through the earth over the course of centuries as it seeks out the subterranean horrors it feeds upon.

The city's sages can usually "steer" the city by magic or by technology (pouring a cauldron of boiling lead down a pit in the shell to the creature's flesh ought to do the trick), but sometimes the creature the city is built in just goes dormant for reasons that are not always clear to the city's inhabitants, causing long periods of the city existing in a single location, punctuated by a sudden change as the creature begins moving again.

Inspiration:  Hieronymous Bosch's weird paintings of people walking around inside hellish living buildings (Bosch's paintings in general should be enough on their own to inspire several monster manuals....)

Edit to add:  Oh, yeah, and Pietr Bruegel had his fair share of monsters and living buildings, as well...


That's awesome, can I steal it please?

It also makes me think how horrifying Doctor Doolittle could be with a little retelling...
Harrying your Prey, the Easy Way: A Hunter's Handbook - the first of what will hopefully be many CharOp efforts on my part. The Blinker - teleport everywhere. An Eladrin Knight/Eldritch Knight. CB != rules source.
Feel free
[spoiler New DM Tips]
  • Trying to solve out-of-game problems (like cheating, bad attitudes, or poor sportsmanship) with in-game solutions will almost always result in failure, and will probably make matters worse.
  • Gun Safety Rule #5: Never point the gun at anything you don't intend to destroy. (Never introduce a character, PC, NPC, Villain, or fate of the world into even the possibility of a deadly combat or other dangerous situation, unless you are prepared to destroy it instantly and completely forever.)
  • Know your group's character sheets, and check them over carefully. You don't want surprises, but, more importantly, they are a gold mine of ideas!
  • "If it ain't broke, don't fix it." It's a problem if the players aren't having fun and it interferes with a DM's ability to run the game effectively; if it's not a problem, 'fixing' at best does little to help, and at worst causes problems that didn't exist before.
  • "Hulk Smash" characters are a bad match for open-ended exploration in crowds of civilians; get them out of civilization where they can break things and kill monsters in peace.
  • Success is not necessarily the same thing as killing an opponent. Failure is not necessarily the same thing as dying.
  • Failure is always an option. And it's a fine option, too, as long as failure is interesting, entertaining, and fun!
[/spoiler] The New DM's Group Horror in RPGs "This is exactly what the Leprechauns want you to believe!" - Merb101 "Broken or not, unbalanced or not, if something seems to be preventing the game from being enjoyable, something has to give: either that thing, or other aspects of the game, or your idea of what's enjoyable." - Centauri
Thanks.  In return, have this
Harrying your Prey, the Easy Way: A Hunter's Handbook - the first of what will hopefully be many CharOp efforts on my part. The Blinker - teleport everywhere. An Eladrin Knight/Eldritch Knight. CB != rules source.
"This is no cave..."
Back to Basics - A Guide to Basic Attacks You might be playing DnD wrong if... "Only two things are infinite, the universe and human stupidity, and I'm not sure about the former." Albert Einstein
The city crawls:  it is carved into the shell of a titanic burrowing mollusc, dissolving its way through the earth over the course of centuries as it seeks out the subterranean horrors it feeds upon.

The city's sages can usually "steer" the city by magic or by technology (pouring a cauldron of boiling lead down a pit in the shell to the creature's flesh ought to do the trick), but sometimes the creature the city is built in just goes dormant for reasons that are not always clear to the city's inhabitants, causing long periods of the city existing in a single location, punctuated by a sudden change as the creature begins moving again.

Inspiration:  Hieronymous Bosch's weird paintings of people walking around inside hellish living buildings (Bosch's paintings in general should be enough on their own to inspire several monster manuals....)

Edit to add:  Oh, yeah, and Pietr Bruegel had his fair share of monsters and living buildings, as well...


Super cool. Giant turtles with a city on it's back is cool, but that is cooler still

My suggestion is only create specific areas as they are needed for the story. You can say what you pretty much just typed, use that as the basic description, then see where the players want to go, what areas you need to flesh out. Don't build the city up front (though I understand a lot of people enjoy that kind of creativity) but let it be developed through exploration.

I agree 100% with this - just start with a small core and maybe set your tone of the city (eg: Is it like Berlin where all the trees are numbered and the pathways are as wide as the road? Is it like London where the streets are thin, the road bends constantly and all the staircases are tiny spiral staircases? Is street music popular?

That said, leave a lot loose so you can make the city one that the players would enjoy - if the party ends up a violent party, you can make there be violent suburbs and big battle arenas against underground monsters. If the party ends up liking to save the day without ever drawing a sword, then you can make it more Nior mystery and 24/7 'rain.'