Hi, I need GM advice.
The setting:
I am going to GM a campaign for pathfinder set in a post-apocalyptic/post-modern anime style setting. It takes place in a super communist government that is isolationist and repressive. Once a large city that has fallen to ruin, decrepit skyscrapers and modern architecture haunt the landscape. All technology is lost or horded by the government, but magic cannot be taken away, only suppressed. It will take place in a high-school setting, and I would like to somehow incorporate the underdark (possibly covert gov't involvement).
My background:
I am new to Pathfinder as a GM, and switched-over from 4.0 when PF came-out as a player. I had a short run as DM for 4.0. This is going to be a solo campaign for my boyfriend and I. My GM style is creative and fantastic, I am a great improviser and role-player but I tend to overlook alot of rules, and according to my BF, have never learned them in the first place. He wants to play more by the book, and I want to play loose and keep it simple for me, I need to find a balance.
My questions:
1. Are there any APs or moduals or anything available now or in the future like this? I think that pre-written material will make it easier on me.
2. How would you GM such a setting for PF? What monsters, items (ancient/modern), equipment, or rules would you use?
3. Do you have any suggestions to make GMing PF easier for a newbie?
4. How would you interpret the classes to fit the setting?
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Its not PF, but if you are looking for pre-written flulff then some post apocalyptic settings that incorporate magic that I can think of are Rifts, Cthulhutech (robotech + mythos) and Fading Suns (Dune-esque scifi - I think they did a d20 version - probably out of print)
Dark Legacies by Red Spire Press was also quite good, but might be out of print (pdfs might be available). It was d20 with a low magic rules set.
What style of anime? Serial Project Laine? Tank Police? or Samurai X?
Hi, I need GM advice.
The setting:
I am going to GM a campaign for pathfinder set in a post-apocalyptic/post-modern anime style setting. It takes place in a super communist government that is isolationist and repressive. Once a large city that has fallen to ruin, decrepit skyscrapers and modern architecture haunt the landscape. All technology is lost or horded by the government, but magic cannot be taken away, only suppressed. It will take place in a high-school setting, and I would like to somehow incorporate the underdark (possibly covert gov't involvement).
My background:
I am new to Pathfinder as a GM, and switched-over from 4.0 when PF came-out as a player. I had a short run as DM for 4.0. This is going to be a solo campaign for my boyfriend and I. My GM style is creative and fantastic, I am a great improviser and role-player but I tend to overlook alot of rules, and according to my BF, have never learned them in the first place. He wants to play more by the book, and I want to play loose and keep it simple for me, I need to find a balance.
My questions:
1. Are there any APs or moduals or anything available now or in the future like this? I think that pre-written material will make it easier on me.
2. How would you GM such a setting for PF? What monsters, items (ancient/modern), equipment, or rules would you use?
3. Do you have any suggestions to make GMing PF easier for a newbie?
4. How would you interpret the classes to fit the setting?
1. Unfortunately no. There is to date no pathfinder modern/future material that I know of. You could pick up d20 modern material and port it to pathfinder the way you would port other 3.x material to pathfinder but there are no modules or AP's that support this kind of setting that are exclusively pathfinder.
Mind you if you dont mind porting things, books that would help you from d20 modern are: The Core rulebook for d20 modern, D20 Modern future, and future tech (for the government technology), d20 apocalypse (for the post apocalyptical setting). I am not sure if there is a good module you can pull from, but those products will provide a good foundation. You can also check urban arcana for more fantastical elements (besides the basic stuff provided in d20 core rules)
It will be alot of work though as d20 modern is actually 3.0 based (i believe) and not 3.5. So using it in the pathfinder rules will require some attention to detail. The d20 apocalypse book though will provide good ideas on just running that style of game, even without it's rules content.
Keep in mind the main rules of d20 modern are available in the SRD which can be found here. So definately have a look before you start buying books. See if the general feel of it will fit your needs and then consider things like apocalypse or future.
2. I am actually planning something sort of like this based on the dark tower series, and i plan on pulling from a number of sources including d20 modern/future/apocalypse and making up my own material. I expect it to be labor intensive unless i get really good news from Super Genius Games on there Pathfinder modern product making progress)
3. Well you are actually taking on a setting that will make it rather hard. Presumably this is the story you really want to tell, so go for it, but if you play in a more traditional fantasy setting there will be ALOT more material to help you.
Also this is a 1 on 1 adventure right? First things first, this cant be all about combat unless you want to run a couple dm npcs yourself (which is inadvisable for a new dm). So focus on the story, and focus on the individual's goals, strengths, and abilities. If he's a tricky, stealthy rogue, base the story around that. If he is a bookworm wizard, focus on studying and attaining powerful magics. With only one player in the game focusing on them means they always get to shine, something that doesnt happen in a normal sized party.
4. Most of them are straightfoward, though depending on the proliferation of firearms in your world you may want to change starting proficiencies. Like fighters may be proficient with firearms instead of martial weapons if they are more likely to use a rifle then a longsword.
The bulk however will work just fine depending on how much things are suppressed. Keep in mind that pathfinder classes can be pretty dependent on magic items, so if they are scarce in your world you will either need to replace them with inherent bonuses or reduce challenges if your pc's cant get easy access to basic magic items.
1. Unfortunately no. There is to date no pathfinder modern/future material that I know of. You could pick up d20 modern material and port it to pathfinder the way you would port other 3.x material to pathfinder but there are no modules or AP's that support this kind of setting that are exclusively pathfinder.
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Also this is a 1 on 1 adventure right? First things first, this cant be all about combat unless you want to run a couple dm npcs yourself (which is inadvisable for a new dm). So focus on the story, and focus on the individual's goals, strengths, and abilities. If he's a tricky, stealthy rogue, base the story around that. If he is a bookworm wizard, focus on studying and attaining powerful magics. With only one player in the game focusing on them means they always get to shine, something that doesnt happen in a normal sized party.
Its not PF, but if you are looking for pre-written flulff then some post apocalyptic settings that incorporate magic that I can think of are Rifts, Cthulhutech (robotech + mythos) and Fading Suns (Dune-esque scifi - I think they did a d20 version - probably out of print)
Dark Legacies by Red Spire Press was also quite good, but might be out of print (pdfs might be available). It was d20 with a low magic rules set.
What style of anime? Serial Project Laine? Tank Police? or Samurai X?
Thank you Kolokotroni and Robert for your advice. I think porting will be difficult for me. I also want to play Pathfinder, I appreciate the other options but rather stick with what I'm used to. I'm trying to keep it as simple as possible, but I will definitely look into the SRD for d20 modern, and the others you mentioned. Would the Dark Tower series be something useful to me also?
This is post-apocalyptic and post-modern, so I think I can avoid using future/modern material since much has been lost or taken away by the strict governmental forces.
Also this is a solo adventure BUT there will be a party of 4 characters. I will be playing two characters along with the two my boyfriend plays. It may be difficult but I am confident in my role-playing.
As for anime... I mostly I read manga. The feel and style of Trinity Blood and Vampire knight are similar to the flavor I want to create. However, I was very inspired by a novel, later made manga and movie, called Battle Royale by Koushun Takami. Of course this is Pathfinder, as for Shoujo or Shonen... there will be a little of both, shoujo for roleplaying and shonen for the fights.
This is the overall story I want to tell. I am willing to adjust to make it work for pathfinder, I am determined. This is how I think:
1) Isn't there a way to manipulate the settings of APs or modules?
2) If I find an adventure path that is very close to what I am looking for, battle wise, can't I just change the overall flavor and adapt the plot/setting?
Ok well if you want to manipulate something in the setting to suite you, the place to start is Golarion (the campaign setting) is Cheliax. It is a lawful evil totalitarion realm run by devil worshipers. They took over when the country's diety Aroden died. Make Aroden the god of the whole planet, and his death would definately bring on the an apocalypse type setting.
As for manipulatiing APs? Its really really hard. I mean, going from post apocalyptic to fantasy or vice versa isnt like moving between 2 fantasy settings. The look, the feel, and all the rules are different. If you want the game to FEEL like your setting, it will require ALOT of work on your end. Every non-monster enemy needs to be reconsidered, rules for high technology (if you decide to include it) needs to come from somewhere. It simply isnt available in pathfinder.
There are no existing pathfinder AP's that would really suit your needs. The best one is A council of thieves which is set in cheliax, but thats really it's only selling point for your idea. You are better off with your own story because really the best you could get from an adventure path is a few character ideas. You would have to rebuild them, redesign encounters and rewrite the story.
Also is this government going to play a role in the campaign? If so then you still need these modern/future rules if the government agents are going to use them. At the very least you need some basic foundation for when the party goes head to head with government agents.
But lets start with the basics.
What do you want from this campaign? Will the party be struggling to survive in this world? Escape to a freer land? Take down the evil government? What are you actually looking for the party to accomplish.
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http://paizo.com/store/downloads/pathfinder/pathfinderModules/35E/v5748btpy 81qt
Crucible of chaos involves exploring the ruins of an ancient flying city. Its creepy and dangerous and you can swap the jungle out for anywhere really.
You could swap out the shoggoth for an Akira type monstrosity
Battle royale is the one with the high school kids fighting to the death on an island? Supposed to show the crazyness of the education system? The Carnival of Tears module with some adaptation might sort of fit.
The magic acadamy for kids from the Korvosa sourcebook might also work.
Also is this government going to play a role in the campaign?
But lets start with the basics.
What do you want from this campaign? Will the party be struggling to survive in this world? Escape to a freer land? Take down the evil government? What are you actually looking for the party to accomplish.
Yes the government will play a large role. But not right away, probably at higher lvl (starting around 6 or so). I'm not planning on the government official/agents using future weapons. That would only give society the knowledge of the weapons, and create a high risk of civilians getting a hold of these weapons or even recreating them their selfs. So with this in consideration the government has decided to go ahead and destroy any existing futuristic weapons, so the threat is lost. The government will be mostly chaotic evil or lawful evil spell casters and some very talented ninja like fighters. I'm also debated if I want this government to side with Underdark forces to increase their power. Or do I want the Underdark to be a completely different threat against civilians?
From this campaign I want to have the characters struggling to fight the corrupted world. There will be a strong need to bring order to chaos. Also, this is a chauvinist world, to the extreme. Even the good, sane man would try and bring justice to the treatment of females. In short I see the party first trying to help some of their fellow female classmates/friends. Then more importantly looking for a way to escape this world. When the difficult reality of escape sinks in, they may find that it will be too complicated to safety free all the ones the love. Defeating the evil government is the may be there only hope.
Sorry this still is rough draft ideas, but does it make since?
http://paizo.com/store/downloads/pathfinder/pathfinderModules/35E/v5748btpy 81qt
Crucible of chaos involves exploring the ruins of an ancient flying city. Its creepy and dangerous and you can swap the jungle out for anywhere really.
** spoiler omitted **
Battle royale is the one with the high school kids fighting to the death on an island? Supposed to show the crazyness of the education system? The Carnival of Tears module with some adaptation might sort of fit.
The magic acadamy for kids from the Korvosa sourcebook might also work.
Hmmm I looked at the Crucible of Chaos, it sounds exciting, but it's only for 8th lvl characters??
Yes that's Battle Royale. It shows the craziness of a corrupt government and education system, similar to what I'm imagining for my adventure. Instead of Battling each other I am going to have them battle for their own lives and freedom. I actually have the Carnival of Tears module, so it has crossed my mind, but the story will have to be altered quite a bit. I haven't heard of the magic academy for kids... link?
Also, Thanks again. I'm open to criticism and any ideas. I'm just keeping my fingers crossed so that maybe one day Pathfinder will create a module for a post-apocalyptic world.
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Heres a picture of some of the students fighting psuedodragons that are likely trying to kill their familiars.
http://paizo.com/store/downloads/pathfinder/pathfinderChronicles/35E/v5748b tpy81xy
Also try searching for Mike McArtor and Acadamae on the boards for more info.
And ze wiki http://pathfinder.wikia.com/wiki/Acadamae
For a radically simpler approach, why don't you just consider backing off a little on the technology thing?
Have the ancient technology be a completely lost art the likes of which only exists in legend or strange structure. Like how constructs are powered by magic, there were once technologies infused with magic (or steam) that brought them to life, such as airships, trains, and other such. Just no computers/cell-phones/machine-guns.
I guess this is more in the direction of some of the Final Fantasy games or Myazaki (or steam-punk, or ebberon), but you could more easily bridge the anime feel with a more low-technology setting like PF. It's more of an alternate universe thing, ancient technology infused with a modern sensibility, the anime/manga style really lets you pull off clashing concepts like this easier.
Anyway, sounds awesome and the imagery is very evocative of rich role-playing... Good Luck!
You might get some use out of Green Ronin's Red Star Campaign Setting, based on the infrequently released comic of the same name.
Eberron (1 B, 2 Rs) for 3.5/4e D&D had some good examples of highly magical lost civilizations that were in shot form were nuked into rubble that 'modern' adventures are plundering.
Post-apocalyptic settings don't need to come from high tech. High Magic of fallen empires is also doable (and one you don't see in fiction much).
Go look up Dark Sun, which was an old 2e setting that is pure fantasy post-apocalyptic.
Adding an amine/manga flavor is possible depending on the tropes (like TV tropes) you are thinking of using. However I would point out that the power level of Pathfinder still follows some of the 3e scale. 1st to 5th is going to be "normal human" scale. 5th level being the best a normal person would achieve, like an Einstein. 6th+ is where you start seeing literary hero power, like mortal Greek heroes. I've always seen 10+ as martial arts film level, like Crouching Tiger Hidden Dragon.
I agree, check out the d20 Modern SRD and don't miss out on the Future documents. Stuff like radiation poisoning can be made "magical" in nature. And do read through the disease and curse section of the Core book, and use them plus make a few of your own.
I'll post more on canalizing d20 Modern for Pathfinder when I'm not posting from an iPod.
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WoTC's 3.5 book the Tome of Battle - Book of 9 Swords has lots of martial arty anime flavour too.
I wonder if there is a full metal alchemist supplement out there..That's definitely a series about discovering how corrupt and evil the system is.
SLA industries has many of the themes you are talking about, but its a sci fi game - it was poorly edited and unevenly realized, but its free now so hey.
D20 Darwins World comes to mind. As backdrop material you may be able to pick up GURPS horseclans or newsun.
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Once you do start building your campaign, regardless of what rules you end up using, I really suggest using some form of wiki / notetaking tool.
Obsidian portal is a pretty full featured wiki set up for rpg campaigns.
Tiddlywiki is a nice, simple to use wiki set up. Here is an example of it being used by players to record an ongoing campaign from a few years back. Tiddlyspot provides free hosting for tiddlywikis.
This will help a lot when it comes time to flesh out your game world and the supporting cast of thousands
I'll try to think about what else I found helpful when I was gming.
I've decided to lay off on the technology idea. Utilizing the idea of High Magic of fallen empires can definitely work for this adventure. Miyazaki and Final Fantasy are definitely a inspiration. Alot of anime/manga heroes can portray a feel of higher PF character's. Most of the time main heroes are high schoolers saving the world or fighting of evil villains.
I've heard good things about Dark Sun, but I'd have to convert and that may will be too much work for me :P I'm starting to build/write the adventure now. Thanks for the wiki links, I'll check them out.
Okay, here is the original d20 Modern SRD page
http://www.wizards.com/default.asp?x=d20/article/msrd
While you have decided to back off the technology side there are still interesting options. Take the Future Environments RTF file, which has some good and still usable guidelines for toxic atmospheres (localized), different gravity (don't see that in a tech apocalypse). Also in Future Exobiology there is the extraterrestrial template you could apply to monsters to make them even stranger. Just replace Psionic Resistance for spell resistance and Psionic Power for any Wizard/Sorc spell of 2nd level or lower.
As to using the gun entries in Modern and Future, remember to look for something that is of similar power in Pathfinder to equate it to. In this case take a look at Scorching Ray, Acid Arrow, or any other Ray spell. Acid Arrow does 2d4 damage and requires a ranged touch attack (which means no armor or shield) vs a Walther PPK (2d4 ranged not-touch attack, increment 30 ft., clip 7 shoots). Not quite as good as a Wand of Acid Arrow but if you start looking at spell damage and the wands or staves you can make out of them, that should give you a good rough idea of what NPCs could possibly have them as 'artifacts'. A Laser Rife (3d8, 50 shot, 80 ft.) isn't much better then most 2nd or 3rd level attack magic wand. Especially after applying a -4 non-proficiency penalty.
Something to also remember, is that while a certain 'Frost' person loathes the concepts of firearms in Golarion, the Campaign Setting manual gives explicit rules on their creation and use. Lasers and the like could be explained through Magic Item Creation through the Master Craftsman Feat, the ability to duplicate or replicate a variety of spell-like effects.
In a post apocalyptic game ... The variety of Planes, Heaven, Hell and everything in between, collapsed in on itself, creating a singluar massive 'reality' in which the living wage an endless war against a world gone mad, in which there is a five-way war between the remanents of Heaven, the 'benevolent dictators' of the remaining survivors of the Apocalypse, the Dragons, would be New Gods of the Overworld, the Monstrous Races (Giants, Goblins, Orcs etc), eager to stake their own claim and pay back untold generations of suffering and oppression at the hands of the 'Survivors', and the Demons and Devils, both of whom have enslaved large populations of all of the above in an attempt to settle once and for all the Blood War and then dominate the remaining ruins of everything.
If you intend to make it a 'Modern' campaign and all of these mythological creatures springing up are completely outside of normal Human experience, treat Dwarves Elves, Half-Orcs and the like as 'sympathetic mutations' while Orcs, Goblins and Giants are almost always 'hostile mutations', so far diverged from Humanity due to the cataclysm that they are, biologically and/or culturally clinically insane while being socially incompatible with Humanity and the 'Sympathetics'. Psychic variations (Spell-users, make them very rare) are further mutations that can unexplicably tap into the mutating energies that the Apocalypse unleashed and use it to perform supernatural feats, often subtly corrupting themselves as they do so (higher level Spellcasters could suffer from physical deformities or mental problems with little real impact on their game mechanics)
Dragons are the result of abominable genetic research grown overlarge and hyper intelligent as the byproducts of the Apocalypse interacted with their tortured bodies. Expect no mercy to anything on two legs from these guys. Physically powerful with an inherent access to the 'psychic' powers (Spells) and inhumanly brilliant and sadistic minds, Dragons are basically the 'We are going to !@#$ you up so badly the english language doesn't have the depth to describe it!' monsters of such a Campaign. There is no middle group, no common enemy, no shared values.
Demons, Devils and the Celestial Host are hyper-evolved Mutations. The 'Celestials' dream of turning all of Humankind and the Sympathetics into their own kind and trying to establish a utopia in this shattered world. They're arguably either selfless altrusits or benevolent dictators, depending upon creed (Alignment) and their various powers, but ultimately they're the best hope for the Survivors and their allies.
Devils are the same as the Celestials, but with a darker twist, believing mankind caused the Apocalypse and that only the best of the species should be chosen to join them, the rest should be kept around as slave labour and soldiers, and perhaps even cattle to feed on. Still, they have great martial skill and possibly access to the last self-automated plants that churn out thousands of high-end weapons such as pulse laser rifles (Magic Missle-shooting Rifles, CL 9th) and Battle-Droids (Golemns).
Demons are a step above the Dragons in that they at least will allow some of the survivors to join their ranks before unleashing a hell of debauchery and soul-rending terror on what remains of the world. Monstrously deformed and insanely jealous of the Devils and the Celestials, the Demons are the force that corrupted the 'Hostile' Mutations into the current genocidal rampage, and unlike their sibling races have no inherent pecking order or over-arching goal that unites potential rivals. You hold what you have the strength to hold, and must hold it against all comers or become fodder yourself. It could very well be that the Demons are the ones who started the Apocalypse or created the Dragons themselves.
Either way, sounds like an awesome campaign. I would recommend the Curse of the Crimson Throne. Change the theme a bit to a rad-blasted wasteland where the Orcs live, and the Crown of Fangs itself be the remains of a potent Dragon that is still psychicly alive, manipulating it's wearer. The cultists of Zon'Kuthon are Demon-followers, expecting to be 'remade' into the 'perfect life-forms' as reward for their services, and the Shoanti, Ulfen, Varisian and other 'primitive' races are the survivors of the 'Overground', while the Chelaxian, Tian, Vudrani, Taldor and other so-called 'civilized' races of Mankind survived by hiding out in thousands of sheltered, well-protected and -stocked bunkers to return to the surface a few hundred years ago, and have been pushing out into the world, pushing aside Survivor and Mutant alike to 'reclaim' their former lands, now rad-scarred and filled with twisted wildlife their dated records have little information on.
Why didn't I remember this before. I think your post reminded me HalfOrcHeavyMetal. Golarion (the Pathfinder Setting) has had a apocalyptic event. The Age of Darkness was a period in the setting where the sun was blocked for 1000 years by a massive meteorite impact brought down by Aboleths to punish the human kingdom they had created (and that was rebelling against them). At the same time you had Orcs push out from the Darklands (underdark) on to the surface and begin conquering the remaining surface races within their reach.
While the Second Darkness AP isn't itself apocalyptic it deals with that lovely anime theme of people trying to bring the world to an end. The context of it could be changed to be harsher most likely.
There are other equally world shattering events in the Pathfinder Chronicles Setting itself.
Dorje Sylas & HalfOrcHeavyMetal you guys are on the same wavelength as me. The apocalypse in my world began when the planes collapsed on themselves. The details HalfOrcHeavyMetal went into about a 5-way war between the different planes is exactly what I imagined happening. I want to use the idea of Elves, Dwarves, Halfings, and the like as 'sympathetic mutations' and the same with Giants, Orcs, and goblins being 'hostile- mutations'.
Dorje Sylas I think I can take some ideas from the Age of Darkness especially the meteorite blocking out the sun. I imagined this post-apocalyptic world having a change of environment, either a lack of sun created by a meteorite or dust field, or increase of sun/heat due to the collapsing of planes and/or atmosphere/ozone.
Here are some new questions that have developed:
1. If the collapse of planes created the apocalypse, how would that effect deities and religions? Would some gods die or be created?
2. The city where the adventure starts is cut off from the rest of the fallen world and is mostly human, trying to keep 'mutations' out, what are some good ways to create this barrier? A magical force/wall/soldiers?
3. If I want to create a change in the environmental atmosphere, what might be easiest to roleplay, reduces sunlight or increase heat/sun?
Here are some new questions that have developed:1. If the collapse of planes created the apocalypse, how would that effect deities and religions? Would some gods die or be created?
2. The city where the adventure starts is cut off from the rest of the fallen world and is mostly human, trying to keep 'mutations' out, what are some good ways to create this barrier? A magical force/wall/soldiers?
3. If I want to create a change in the environmental atmosphere, what might be easiest to roleplay, reduces sunlight or increase heat/sun?
Good questions... Can't say I have good answers for them, but I'll do my best: (at least you get a bump)
1. However you want. You can orchestrate any number of conflicts and battles between deities, like traditional mythology.
2. Well, either could work. Depending on the nature of the threat, you may or may not need something beyond mundane walls and soldiers.
3. I favor the increase in sun, a hot barren wasteland of epic proportions with horrid beasts stalking the twisted landscape. Still possible to have the occasional oasis or atmospheric anomaly, or "point of light".
Good questions... Can't say I have good answers for them, but I'll do my best: (at least you get a bump)1. However you want. You can orchestrate any number of conflicts and battles between deities, like traditional mythology.
2. Well, either could work. Depending on the nature of the threat, you may or may not need something beyond mundane walls and soldiers.
3. I favor the increase in sun, a hot barren wasteland of epic proportions with horrid beasts stalking the twisted landscape. Still possible to have the occasional oasis or atmospheric anomaly, or "point of light".
1. Agreed. I'd definitely be putting a real emphasis on the fact that the 'Deities' are going hell-for-leather to win this fight. Celestials want to put things back the way they were (With them on top of the pile, naturally), Devils want to put things back together sans the Chaotic and Celestial Realms, and Demons want to keep everything embroiled in this wonderful chaos forever.
Divine Entities will simply have more power to do so, but will be requiring followers to build, supply and maintain 'Shrines' over the landscape to act as foci so that the Deities can actually send their power out more than a few hundred miles from their location, a concept taken equally from the Faerun Time of Troubles and a fun game called Sacrifice, in which PC 'Wizards' had to run around capping mana-fountains with their own unique shrines and altars to be able to cast magic and 'control' an area.On an off-tangent, due to the planar 'smushing', spells that contact other planes or allow travel to other planes must be removed or reworded to allow transport through region that possess aspects of the planes that fused into them.
An off-off-tangent, but imagine the Celestial Realm (such as it is) is now a fusion of Heaven, Elsyium and Nirvana, with a single great mountain, heavily forested and surrounded by lush, rolling hills and thick, primevil forests in which the Celestials dwell in relative harmony with each other and their mortal followers. Alternatively, the Celestial Realm could have also taken some of the Astral Plane with it, and the mark of the beginning of your transformation into a 'higher being' is being able to muster the willpower necessary to 'will' yourself into Flight, bypassing the streets and walkways entirely to fly with the Celestials themselves.
2) For most cities, a thick wall of iron-reinforced stone must suffice, with the soldiers reinforced by militia armed with whatever effective weapons that can be mass-produced cheaply. Soldiers would probably be wearing low-level magical armor and wielding potent long-range and short-range weaponry, such as magic rifles or composite longbows and Cold-Iron weaponry, wherein the Militia would be equipped with Light Crossbows, leather armor and weapons like Maces or Morningstars, intuitive weapons that don't require much training to be proficient with.
A luckier city might very well have an artefact that creates a Forbiddance effect that blocks Demons and Devils from entering (any Celestial that loses their good alignment would probably be blocked as well) as well a variant Hallow effect that causes extreme discomfort in the 'impure' races, Sympathetic or Hostile, the spellwork was powerful but too clumsy to single out 'friendly' races (Or perhaps the caster was an unmitigated bigot and didn't want the 'unclean' in their city ... or even their world!), such as a -5 to all rolls.
Keeping said artefact intact and powered could belong to a singular organisation that has decided to use their power to hold the city to effective ransom in exchange for the artefact's continued functioning.
3) ... I'll have to get back to you. Work is calling. Sorry!
New questions...
and intresting answers so far. Thanks everyone.
Have you seen Gun Parade March?
A high school was existing in the computers. To tell you about the outside world would be a spoiler.
You know The Matrix is post apocolyptic.
There's another one, Interlude or something.
The simulation gradually starts to break down, but more details would be a spoiler as well.
As for your project, I do not recommend D20 modern, like 4th edition, it's put back together wrong. You are better off converting over gun rules in the 3.5 DMG. The underdark can be where all the monsters and dragons survived while the modern world was running it's course.
I think there is a movie Troll which can inspire you.