6-Room Dungeon 12: Hell Gate

Coincidentally, some hellish stuff in my games.

My Theros party in a Clark Ashton Smith-inspired adventure in the floating ice skull island of a prehistoric wom wizard were considering fleeing and looked through one last door to see a puppy in a torture chamber with cells. A  dwarf lady with a beard, elf without arms and a cell of treasure.  So they went in and puppy laughed and it said mean stuff. Was an Ice devil. Bad news in 5th ed. Good warmup before the worm wizard.

My weekly D&D5 game party on an island of folk horror villages. Village one, they drove off fish folk and crashed the fishing economy. Party helping restore trade and so helping the brewing and farming industries. 

Next village, they tolerated the angler fish cult who hated the other fish folk so party tolerated them marrying men to their moronic fish goddess Lampgulp and fuse with her flesh until eternity. There was a village with weird memory loss patients in an asylum and lots of wizards. Then last session they found anti-mutant swamp folk. Party disgusted and went to look at freakshow to learn about mutants. Saw locals tormenting small muties in a drain and a party halfling offered to get them out but put them in his bag of holding. At the freakshow, they beat up the owner, killed him, set the mutants free. Then burned the tents. They escaped in a cave and saw a vast lake of filth, the God Abhoth spawning small mutants. They found a way out and the Mayor was waiting.  The mayor who hated the freakshow told them to leave before the mob found them. 

Next village the saw a rich green hilltop of nice houses around it all surrounded by a white fence. Everywhere else was filth with mine pits and dirty mounds and rude wooden shacks. So they went to see a witch and sold orc corpses to sea trolls and on way home late saw the posh villages are alight in green flame from a well. Naked and robed locals were pushing someone in a well. So party killed them all to save the stranger while the villagers watched in horror and fled. Three large angry mobs formed. One was smashing shops on the way, others beating drums and burning an effigy and another led by an insane opportunist. 

So party fled all night through a swamp. Had a rest before going to village in sight and 3 werewolves attacked. One got roasted by the rescued strangers' fireball and she saved the other two from death and they reverted to women. Had rest and tied resentful and silent women's arms. They arived in village that seemed into hunting and had lots of wolves. Sheriff and posse demanded women be freed, party hand over weapons and come to the courthouse for questioning. So party killed the cops and the women broke free and fled. 

The party spent another day and night crawling through swamps exhausted, they arrived in the friendly but decadent Pig Town where they were welcome. Even local pig orcs helped tell other orcs no homicidal strangers were in area. The corpulent hedonist nobles welcomed the party and invited them to feast tomorrow. Was very satisfying to exhaust and chase players for days. I thought they got along with some jerk villages pretty well before this. While resting Glub Glub the the singing barbarian was getting suspicious about this village. Priest detected the rich were evil supernatural beings. Party tried to get along with poor but because the halfling had a piglet in a fancy costume the commoners shunned them. Local priest of the Sun-Boar seemed to be pro light but was evil fat rich bastard too. While glub glub and priest and the rescued stranger a real priest of light discussed what to do the bored halfling instead played with magic beans. 

First grew a fabulous tree of magic fruit. The second a 60 foot high pyramid releasing a mummy lord. Others saw this and The barbarian jumped out the window berserk. Dwarf ran down stairs and buffed most of team. Priest upstairs was fireballing and zapping the mummy with spells. He kept uncursing and healing party. It was a way too hard battle where the halfling was knocked out. The huge broad-jowled sheriff joined in with a magic halberd. Lots of great teamwork and the barbarian went in the pyramid and smashed the mummy heart jar. I rewarded them with lots of loot and they all knew it was a near TPK. The light priest who was casting from the inn said the halfling deserved squat for playing with beans. The locals cheered the heroes who saved the village from the mysterious pyramid and all the local pigs squealed with delight. 

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This is the final in this set of tables, but I'm doing a second set to expand this series. I might combine and edit final set. Id consider making it for charitry on drive-through but id rather it go to charity as i have to do lots of paperwork on earnings and I can't be bothered. It seems a feasible product.

1 Redbrick
2 Goblin Mine
3 Gothic Tomb
4 Magic Mansion
5 Glacial Chasm
6 Jungle Shrine
7 Underland Cavern
8 Auldwood Grove
9 Sunken City
10 Desert Ruin
11 Eldritch Monolith
12 Hell Gate

This is for medieval-style portals to hell.
Its not fair or nice.

Im considering a game where dnd5 party get to plane travel by swaping with their local incarnations or past lives so each game they can respec their class/sill/feats/spells whatever on a new character sheet. We wou;d learn more about the game anmd people could try weird stuff. People can return to old worlds and update their character. Even if they died on the new plane they would have the skills of their local cosm or perhaps a player misfires and has a old buiold on the wrong world.

https://elfmaidsandoctopi.blogspot.com/2021/04/planar-emanations-influences.html
https://elfmaidsandoctopi.blogspot.com/2021/01/myriad-petty-planes-of-multiverse-pt1.html
https://elfmaidsandoctopi.blogspot.com/2021/02/myriad-petty-planes-of-multiverse-pt2.html

Do look at Bruegel's or Bosh landscapes of hell and other medieval images for ideas. 

The Netherworlds of the Seven Hells
Their are seven hells
-1 Underworld a gloomy miserable place for unclaimed souls, a gateway region with various old gods and titans and tiamat have been imprisoned in crumbling palaces and kingdoms. There are links to the void, nightmare realm and remnants of the ancient underworld of the Dawn age underworld before aeons of cosmic war. The rich who were buried well and keep getting sacrifices live better. Benevolent cthonic gods bring the fructifying powers of the underworld to the vegetation and fertility of the mortal world. The roots of the world tree are here gnawed by Nidhog the dragon of entropy. The first gate of hell is guarded the judges of the dead whe send the wicked beyond to the apocalypse. Their are many beings here not allied with hell like dragons, underworld spirits or imprisoned "dead" gods, dragons and giants of the ancients who all seek release but channel power to their cults. The great dragonspawning pits of the mortal realm connect to the great lair of Tiamat in her palace readying her army for the last battle  

-2 Apocalypse, an eternal plague wracked and war ravaged wasteland of walking dead. The dead here deal with sadistic inversions of the mortal realm lives. All have rotting flesh, disease, hunger, vermin and bodily torments. The dead here are slowly flensed of flesh but many carry their own hides and tie them like robes or belts or capes. The richer you were the worse your humiliation and attachment to mortality. The horizon has endless silhouettes of ruins with the burning walls of the inferno beyond. 
-3 Inferno a burning realm of torture with legions of devils with pitchforks. The last remnants of the body are purified by devils. Damned souls are kept in pits or cages or torture machines and tormentd by devils with pitchforks. Devils are rewarded for cruelty, domination and extracting new contracts from the damned. Some damned become larvae or mindless lemures, others become imps. Volcanoes, boiling lakes of blood anf burning jets og gas make travel dangerous off road. Hell tainted fire elementals visit here also 

-4 Virkan the hell bogs, a vast swampy jungle wetland with swarms, mutant dinosaurs, ruins of drowned civilisations. The damned here are infested with vermin like crabs, flies, worms or wasps gnawing on them constantly. They are feverish and often barely lucid. Prehuman snake, lizard and amphibian peoples serving hell live here and inhabit many of the ruins. This place is a paradise for them, and they use the damned as slaves or for food on their bug farms. Many rivers of the underworld flow here, including rivers of filth, hacked up corpses, zombies or edged weapons. Parts of the world tree grow here and green and black dragons dwell here. Devils here tend to be more scaly. Giant bugs thrive here. Corrupted naga, lamia, medusa, basilisks and other reptilian horrors live here too. The waters and mud are choked with rotting corpses and bones. You may uncover helpless, immobile, moaning bodies of the damed buried in muck or under waters. Undead may arise from the swamp anywhere and many protest their innocence as their bodies attack
-5 Kanos the ice hell a great glacier filled snowy wasteland. Damned here are frozen in stasis for future torments. Some can perceive the whole time and go mad. Devils and the inhabitants put on awful performances for them. They will saw open blocks to eat the flesh within delight. Yetis and elemental cold creatures dwell here. Damned frost giants, ogres, trolls and white dragons love it here, it is paradise. Various glaciers are rulled by local factions and the greatest is that of the ruler. Rivers of hell flow deep below  
-6 Mallus a dark bleak wastland of scarred rocks, ruins, thorn forests, burning trees and vast piles of bones. Fortified walls and roads cross the realm. Devils rule from ruined castles and towers where they torment damned and undead. They remove souls from bodies creating various non coporeal spiritual undead and the bodies are made coporeal undead. Their are rebel devils living alone ion caves and ruins who hope they will get their jobs back and may see outsiders as means to remove their replacements. Armies of hell march here exterminating vermin which might signify invasions of hell as this hell is one of the last defences. Great sentient seige engines wander about while not defending. Sometimes a demonic, elemental or angelic host enters here to battle and an awful war begins. Ruined factories and machines lie from an ade where hell was more automated and there are connections to the boiler room of hell. Lazy devils grew soft so the machine age was abandoned 

-7 Abadoth the city of the damned in a wasteland of fire and darkness with lakes of boiling blood. Most of hell is a single vast continent spanning city. Regions are ruined, many are horrendous ghettos with damed and devils cramped in squalor in crumbling apartments. Walls and gates divide the regions. Vast districts of record warehouses, treasuries and bureaucratic offices. Many inhabitants struggle to keep awful jobs, poor housing and face centuries of government red tape to improve their lot. There are links to hells sewers, boiler room and libraries. Many students of the black library live here outside school. Drink, vice, corruption, crime and worse are normal here. Devils are firmly in charge and imp spies are everywhere. The central palace of the ruler of hell towers over the city and they say it is possible to reach the mortal world.  

Other Netherworld Interplanar realms
There are sub planes linking hells you might try and travel through to avoid scrutiny of hell

-1 Hells Sewers are famous and they say link to many of the worlds cities if you go too deep. Damned, undead and rebel devils lurk here and other horrors
-2 Hells Boiler Room a series of industrial factory for soul processing, abandoned ages ago. People try to use it as a shortcut and regret it. Full of rusted machines, blood splatters and meat. Insane devils left here have gone mad and devolved into demons. Many are ogrish brutes with chains, surgical scars and cruel prosthetics. Many wear strange masks or clown faces. Nightmare entities and all kinds of corrupted planar beings might dwell here as their own kind would destroy them  
-3 The Black Library a tuition-fee-free magic school where anyone could learn wizardry! Students are recruited by imps and sign a contract. They are shown a portal through a mirror or artwork or secret door that was never there before so students can study unlawful spellcraft of witch cults. Most are wizards or sorcerers, some others learn just some petty magic and are guided in the ways of eternal law, wealth, power and domination for pleasure. Many of the wickedest people in history are said to have had secret lessons here. Students here are more likely to be guild or common class than the mortal world. You get taught by planar evil beings and have access to forbidden spells. Good for an evil magoic school campaign 
-4 The Dungeon Domain a sentient dimension with an infinite number of dungeon levels linking to many worlds. It is malicious and spreads hells power. By attracting adventurers and letting them anoint treasure in blood they bring home, the dungeon intrudes into a world more. Some dungeons have survivors of long gone worlds and all kinds of weird humanoids and monsters. Some levels even hav false suns and seem to be vast open spaces. Some levels are prisons for dead unwanted elder gods, titans, dragons and alien gods of the void. 
-5 Roots of The World Tree dwell goblioids, dark faerie, evil gnomes, dwarves and trolls. Many roots of the cosmic tree enter hell and can be used to escape or travel to other hells. Is it safe? Not really. Dark faerie beings desire mortal slaves. Good manners and gifts get you further than war. Whole kingdoms of veings were are ready to awarm against you and will take this grudge wherever you go  
-6 Nightmare Realm intersects the outer void and the dreamlands, but is more chaotic. Darkness and nightmare demons and hags dwell here also. Creatures from your own nightmares will visit you when you come here. The lords of this realm have created isolated fog shrouded realms of misery that dont even know they are not on the mortal world 
-7 Sargassum the seas of hell, which connect to the seven rivers of hell. It boders on other hells as as the sea. There are islands, reefs and ruins on the surface. Cursed huge ships, evil whales and sea monsters are common sights. Giant kelp forests choke regions andlift shipwrecks into the sky like forest trees above the waves. Once a larger landmass was here with civilisation but it was sunk by the lords of hell for arrogance. Most of the action happens underwater, where storms and icebergs are less of a problem. Undersea peoples and monsters are abundant, including dragons and fish folk. Some live in reef-shrouded ruins on the surface to deal with the surface. Many of the damned here toil as slaves or are gnawed by sea creatures. Shipwrecks are common on the sea floor and often occupied by monsters.  

d12 Rivers of Hell
1 Acheron the river of sorrow the main river used by ferry daemons to travel through hell. Dangerous live and aquatic daemons in it make crossing perilous

2 Cocytus the river of lamentations caries helpless, damned spirits and wails of the suffering
3 Lethe the river of forgetfulness, makes you forget your life story and loved ones, which helps you adjust to the afterlife or overcome troubling pasts. Some damned drink here as a final step before they advance to Elysian Fields or Arcadia

4 Phlegethon, the river of fire, a burning river of molten rock, used to punish the damned

5 Styx the river of hatred, used to make oaths to even gods abide by. Grants oath powers and assigns fates with deadly fates full of violence

6 Vaitarna the river of filth full or blood, sewerage and gore. Swarms of flies and diseased miasmas surround it

7 Gyull the freezing river full of dangerous, grinding ice and stabbing icicles. Frozen corpses are common 

8 Atos the river of swords, a flowing, grinding mass of bladed weapons, many rusted and bloodied. Any caught in it is sliced and ground into liquid and swept away

9 Yrgrr, the river of venom, crawling with snakes and a sticky green poison deadly to the touch. Bodies here are devoured by serpents

10 Zorbas, the devouring river, its acid dissolves away flesh and then slowly eats skeletons. Bones, horns and teeth cover the shores and are carried by the current. Slimy gelatinous horrors swim in it 

11 Magakos, the stone river can mineralise life in contact with it for too long and is poisoned with mineral salts anathema to life. Preserved bodies lay around the banks and under the surface. They could be unpetrified, then raised, but they may be ancient  

12 Orandor the river of dreams, delicious and addictive, its scent sraws people nearer. Those who touch it are charmed and drawn in to drown themselves in delight taking a d4 rounds. Content and peaceful bodies flow down the river, their spirits trapped in their own dreams. Devils often fish them out to torture or eat. Exotic lotus flowers, butterflies and sugary crystals  can be found on the banks  

d12 What can Hell do for me?
1 Find love perhaps by with potions or a charm, or hook up with cultists, witches, sylvan beings and supernatural humanoids. Hell's matchmakers will help you find a suitable mate, perhaps a magic one

2 Money is usually obtained by telling you where buried treasure is hidden, or might bring you coins minted in hell, which are addictive and illegal

3 Power through favours of rich patrons in league with hell, which can turn nasty

4 Magic items are often in proportion to your levels, or a sentient item that grows in power with you

5 Magical pets like a nightmare horse, a hellhound, a hellcat, an imp or maybe a baby dragon if you're lucky. They will serve you and destroy your enemies 

6 Diabolical counsellors who offer you schemes and information you need to overcome your enemies. Over time, they seem invaluable. If you can't cast a spell to contact or commune with them, they will visit you in your dreams, but often ask for some seemingly petty favour in return

7 Assign you minions of some non-human species or some human cultists; the higher your station, the more you rule

8 Buff your attributes, possibly if low level, a temporary potion or scroll. High-level souls are more valuable, and 10+ is worth a whole point at high level 10+

9 Improve your social status through support from hell cults, upscale your home and goods

10 Minor ability, lower levels might be able to cast a bonus low-level spell at higher level might be more permanant. 

11 Mutations that prove your dedication and may give you amazing powers if worthy, only fate can decide what powers you will get. You might have to go in hiding or cover your mutations

12 In time of need can summon protective devils. Low level might be a scroll or one use item but higher level may summon an imp or proper devils to your aid or othe creatures like hell hounds

d12 What might Hell do with me in a deal
1 Get you into performing small but escalating tasks like carrying notes or packages on your journey. At first, you won't see subtle effects of your actions, but escalate so it becomes obvious. Your messages might be for others obligated to hell and have horrible results. Will bother you less often we promise if you kill someone for us
2 Make you participate in some kind of secret hell cult or possibly lead or start one

3 Convince others to sell their souls, you can earn freedom or get more wishes as bonus commission

4 Encourage you to get public influence and power using the system, to do it with extra corruption and force. Other agents of hell will boost your message

5 Take this free imp familiar, just feed it a bit of your blood from this extra special nipple

6 Take some mutations to show you are strong and loyal

7 Prove loyalty to the cult by often performing ritual taboo acts like murder

8 Prove loyalty to the cult by often performing ritual taboo acts like murder

9 Adopt an imp, hellcat, fire toad or hellhound and care for it like your life depended on it

10 Aid in Hell's intrusions into this world by helping with summonings and portals 

11 Separate your spirit into various fragments; they can work in different forms, including shadows, lemures, larva, and other non-corporeal beings to increase your torment over potentially millennia. This is like banking for hell's currency backed by tormented souls
12 Get your corpse to work in mindless toil or war for eternity

d12 Hellgate Decor

1 Sulphurous imp turds

2 Unholy sigil or devil signature

3 Chains and manacles (1in6 with bodies)

4 Foul vapours often come from a vent or ornate carved face

5 Evil faces, murals, tiles, relief sculptures (d4 1=grins 2=open mouth 3=snarl 4=laughing)

6 Burning brazier, torches or iron lantern hanging from a chain

7 Torture apparatus (d4 1=iron maiden 2=wrack 3=small cage 4=stocks)

8 Blashphemous old book

9 Idol of a devil or small altar dedicated to a devil

10 Skulls and bones, possibly covering surfaces like an ossuary

11 Smoke, soot and ashes. On the ground, smeared around, drifting in air

12 Murals of frightening scenes (d4 1=torment of the damned 2=hell landscape 3=hells armies at war 4=prophecy with some familiar looking places and persons, possibly an illusion)

 d12 Hellgate Hazzards
1 Evil miasmas (d4 1=disease 2=stinking cloud 3=poison 4=hallucination)
2 Swarm of Vermin (d4 1=rats 2=snakes 3=flies 4=worms)
3 Pit trap with sealing lid, often with rotten corpses (d4 1=spikes 2=snakes 3=water 4=worms)

4 Barred and locked pit (d6 1=well 2=oubliette 3=crawlspace 4=undead 5=corpses 6=mutant) 

5 Lava pool or river, possibly with some kind of crossing or an island in the middle with a chest or altar 

6 Piles of red gold coins with a trident on one side and portraits of hell's nobles on the reverse, curses holders with greed, jealousy, and paranoia

7 Invisible imps or frolicking petty elementals

8 Bubbling pools or river, possibly with a crossing (d4 1=boiling 2=diseased 3=fire toads lair 4=full of snakes 5=undead 6=flammable oil)

9 Trapped chests will be locked with a basic trap and a magic trap like a curse. Some treasure within

10 Hellcat or whispering imp offer to serve you for a year and make your dreams come true if you join hell

11 Jets of flame 

12 Pool of acid

d12 Hell Gate Encounters
1 Hell cultists who meet here or on pilgrimage

2 Hell mercenary soldiers or evil orc warriors

3 Mischievous imps playing some grisly sport

4 Mindless lemures gibbering in a pool of bubbling muck

5 Hellhounds on patrol 1in6 with a cult or undead huntmaster with a horn

6 Shadows arise from the floor and walls or art

7 Ghouls led by a ghast or other 

8 Evil darkness templar priests

9 Diabolical wizard and kobold bodyguards

10 Undead led by (d4 1=priest 2=necromancer 3=undead knight 4=)

11 Hellish Gargoyles

12 Lesser Devil on several patrols

d12 Hell Gate Static Encounters
1 Camp of cultists with mercenaries led by wizards and/or a priests here to worship

2 Coven of witches with imp familiars and other diabolical pets like hell goats, cats or hounds
3 Hag is cooking up someone to feed her brood of larvae. She hangs here to trade these damned souls. She can be helpful if you're polite or give her a kiss or she can be dangerous 

4 Undead hell cultists and damned mercenaries. Led by a more powerful undead 

5 Hell-tainted gargoyles, ready to awake if disturbed, seem to be part of the architecture

6 Lesser devils torturing victims

7 Hell knights are camping with prisoners to sacrifice and treasure. Resting after robbing and murdering (sometimes they are undead or mutated)

8 Bronze bull gorgon ridden by a lesser devil

9 Devil swine in human form, having a magnificent feast served by slaves, happy to talk to strangers, but if angered, change to swine forms

10 Devil with imps playing infernal music with instruments formed or tormented damned souls that scream in pain as played

11 Devil with lesser devil guards or hellhounds, busy at a desk writing contracts. Will calmly offer wishes and diabolical pacts for power

12 Devil is here with job of portaling in other beings to and from hell or call a specific type of devil. May be willing to make a deal

d12 Hell Gate Entrance
1 Porculis gate made to resemble a huge devil face, may slam ot trap intruders. May be an actual living gate that might talk or require a password. The non-living one will have guards like imps or lesser devils or hellhounds who might operate the gate mechanism. A grim stone entry chamber has various passages. It might even talk and require convincing to let you in. It might ask for your willing consent to enter or require you to hail hell with chants and fist pumps

2 A sulphurous pit with a red glow. Climb down into a rough cave with a river of boiling sulfur with a rickety bone bridge. A cult wizard guards the bridge and will destroy it if needed. He will ask questions of intruders to see if they are evil enough to be allowed in. Past the bridge are passages beyond

3 A great bronze door with devil faces with knockers. It knocked a hatch open, and a lesser devil guard demands to know who is there. There may be two guards. Inside is a stone chamber and a wheel mechanism to open the gate, and a bar that the guards can seal the door 

4 An ancient crypt with stairs down to a chamber below. An undead guardian with lesser undead guards the chamber. Sealed stone doors lead beyond. There may be crypts of ancient cultists with treasure here

5 A perfect, carved 25 foot wide 18 foot tunnel mysteriously runs under a distant mountain, long ago. Metal rods on wooden sleepers on gravel are on the floors. After a short distance is a platform area with a ticket booth, guard station and service store room with stairs going beyond past turnstyles. Often held by cultists, lesser devils, shades or undead. Some have other booths selling diabolical scrolls and pamphlets or evil food items operated by imps 

6 A mirror with an ornate frame. With a secret word concealed in the frame, you may pass the surface into a chamber with barred gates leading to various passages. Often guarded by some kind of mirror monster, dopelgangers or evil clones of themselves who enter

7 A painting with an ornate frame. With a secret word concealed in the frame, you may pass the surface into a cavern with various passages. Devils, including imps and lemures, will be here tormenting intruders 

8 A spectacular cave grotto with bubbling pools, eerie vapours and beautiful sparkling mineral formations. Some of these look valuable but crumble if you break them off. The sensitive can see that the formations seem to have malicious smiling features. Many nooks and cavities make excellent hiding spaces for kobolds or even medium-sized creatures. Some of these are cramped passages to the rest of a cave system and may even be hidden among formations in the ceiling or down. Often guarded by hellish, mutated creatures or evil humanoid guards 

9 Volcanic vent with steam and smoke, into a chamber with boiling mud pools, venting steam and burning gas jets. Floor may be steeply angled and various tunnels lead out. Corrupted fire elemental creatures like fire salamanders might dwell here or lesser devils or just imps. Living creatures can't thrive here 

10 Cave chamber with a dark at least 25 foot wide river flowing through it. There are crumbling remains of buildings on both sides. The water is supernatural (d8 1=memory loss 2=drain levels 3=mutagenic 4=poison 5=acid 6=sewerage 7=gore 8=rusty bladed weapons). There may be some kind of crossing or you could get swept away downstream and arrive somewhere in hell. (d4 1=bridge possibly fallen column or giant sword 2=ferry dock 3=rowboats, canoes, raft or barge 4=broken walkway or natural stone arch but you can jump it). Some kind of guardian like a devil, hell knight, evil wizard or hooded cultists, will be here or a supernatural ferryman. Visitors may be challenged about why they are here

11 A great cave into a vast subterranean lake. A beach of unusual coloured sand has some bones and broken boats, and a rickety wooden or bone pier for a boat and a bell. When the bell is rung, a supernatural ferryman comes on a raft or gondola and will carry you down various underground canal paths. It always demands a gold coin but might object to returning you to the entrance if you carry away Hell's treasures. It might even take you to hell instead of out

12 A carved cliff temple with ornate carved rock relief art of cavorting devils. Inside is a chamber with a high ceiling, where the walls and ceiling have more obscene carvings. A diabolical statue of a lord of hell dominates the room with magic, ever-burning torches. At least a devil or several hell gargoyles will be guarding, but may be hidden among carvings or concealed with magic. Visitors may be challenged about why they are here

d12 Hell Gate Sub Rooms
1 Oubliette or cell with a prisoner or corpse
2 Piles of books and documents relating to soul contracts, corrupt nobility and hell's legions
3 Shrine and idol dedicated to a noble of hell
4 Hot cell with a prisoner or a desiccated corpse
5 Cold cell with a prisoner or a frozen corpse
6 Cauldron of boiling oil or stewed human bodies

7 Alchemists lab distiling ichor

8 Imprisoned shadows who attack

9 Imprisoned ghouls who attack

10 Chest with basic and a magic trap with treasure inside

11 Rack with a hellish weapon

12 Lesser devil imprisoned in (d4 1=ice 2=amber 3=coffin 4=bottle)

d12 Hell Gate Main Rooms
1 Room is a huge stomach chamber with a lake of mild acid. Their is a mass of shipwrecks inside and one has become a crude tavern for the damned with a walkway to the various exits. Various devils, imps, undead and cultists are here, possibly trapped somehow or off duty. A succubi, lamia, naga or hag might be here too. The mood is melancholy, and the barkeep offers Hell's Brew in exotic cups. Melancholia here can ensnare occupants in this timeless trap. Some creatures come and go and trade exotic goods like larvae from hell or drugs 
2 A great pit of lava here with hell-tainted fire beings frolicking with imps. Cultists, devils, efreeti or witches might be here relaxing in the glow while cooking and brewing

3 Great square used for drills. May be empty and quiet for a d6 turns. However, forces will arrive for a drill like hell's orcs, kobolds or mercenaries. A hell knight or templar will lead them with a whip

4 Mousoleum for past cultists with burial niches and stone sarcophagi. Undead are very likely, but also cultists might come here for perverse rituals or a necromancer

5 Boiler room, an iron-clad riveted room with rust and blood splatters. Strange machines, venting steam and clanking sounds make it a confusing place. There are large, dangerous-looking machines working without sensible safety rails. There may be chained prisoners working here or damned undead whose souls are in hell, so both pay their debts to Hell. Lesser devils or imps might be here as task masters. This taps into the boiler room of Hell, and all kinds of awful creatures lurk here (d4 1=ogres 2=lesser demons 3=trolls 4=flesh golems) with local flair  (d4 1=frightening clown makeup 2=hook hands 3=chains 4=stitches and mixed body parts) 

6 Forge Room, where slaves and imps craft tools of war, they supply some local factions doing Hell's work. The huge furnace and crucible make the room hot. Smoke and steam fill the room. Constant sounds of clanging metal. An overseer dominates a cadre of workers. Could be kobolds, orcs, humans, gnomes, dwarves or some exotic species. Could also be undead smiths working their eternal damnation. Creatures here are busy and dont sell, but they will trade exotic metals and other materials for basic magi arms and armour

7 Lemure pits either a natural cave pool of mud or a built sewer; there may be a crossing or a point you can jump. Devils and imps come here to torment them or take them away to become imps

8 Ice house, either a natural cave or a stone-cut chamber. Covered in ice and with dangerous icicles everywhere. An ice devil directs undead, hell yeti, and white winter wolves. Ice structures or even walls, walkways, and stairs might divide the room partially or may be used as barriers. Some even have snow or freezing water under the floor ice. This water might be home to more monsters or be dangerous to touch. The ice will have ancient humans and unfamiliar beasts. Yeti saw some blocks open to eat

9 Fire pit with larvae being tormented by several devils with pitchforks. Have a d4+1 barrels of foul things to throw in the pit. Orcs, cultists or kobolds may aid them and learn the lore of hell on the job. It can speed up your next few incarnations.

12 A lake of fire with a bridge to an island with an illusion of piles of coins and several chests. Hell-tainted salamanders guard the chest, led by a devil. The chests are locked, trapped and protected by a spell or curse

d12 Hellgate Feature

1 Inside the huge beating heart of a Devil guarded by golems or devils. If they die the devil appears here in person to kill those who risk its eternal destruction. If heart is damaged enough it stops pumping ichor and the complex shakes and possibly floods with gore. The devil also keeps treasures here but they will be magically trapped 
2 A great flaming chamber with a causeway through lava to an island with a hell monolith. By manipulating magic symbols on the altar you can open a portal to hell. A great flaming elemental or hell cultist fire giant guards the island
3 Throne chamber with elaborate relief rock carvings of devils that emphasise a raised floor area with a mighty noble chair. Cultists may be here to claim it or just pilgrims. They might use it in ceremonies anointing leaders. Sitting in the throne has various functions (d4 1=comune with Hell 2=Change alignment to LE 3=makes voice boom 4=cast command once per round with no visible evidence just a glance while seated). If there is no cult here they will leave a monster or devil to guard it  

4 Palace of death a vast hall in the ancient style but black stone. Statues dedicated to the old underworld or traitor gods surround a stone feast table. A great underwold feast here if eaten will trap you in the underworld. You can enter to underwold propper through an ornate altarpiece artwork but this room is partly on the border of that plane. Living statues or golems may be here to defend it or undead may be here. A petty underworld deity or gatekeeper may be here to guard or welcome 

5 Infernal Machine a great rotating metal spiked pit stories deep, occasionally starts up, grinding creatures trapped in the gore pool below into liquid that drains away. Occasionally, hacked-up bodies and living beings and undead fall through hatches in the roof. A narrow walkway over the pit has an iron control altar at the central axis. A devil usually supervises, and imps make repairs or a cult or might control it (d4 1=mutant clowns 2=flagellant berserkers 3=flesh golems with meathook hands 4=undead templars)  

6 Control room, an ironclad, rivited room with console banks around the room and various screens. Banks of cables and sockets alongside machines like player pianos running computational scrolls. This may be automated with guard automatons but it may me a semi-sentient machine. Undead, imps or undead may operate it with a supervisor of higher rank. It monitors dimensional portals to hell and sends devils to the required locations. Machines have keys with diabolical sigils on them that can dial up devils and locations. If anything goes wrong, other stations report it, and a greater devil is sent by management in hell through an elevator from below.

7 Black Library Chamber, connected to the planar library of hell. Librarian devils or undead wizards may be working here. Students wizards here for free tuition may be studying or passing through. Doors here lead to other dimensions via mirrors and paintings. Books of ancient lore used for spell research are often specialised here

8 Crumbling cavern with glowing fungus and an ancient ziggurat. Mutant creatures live in the bog around it, and the top has an altar and a devil. Offerings or sacrifices here call a greater devil, and quite often, a cult comes here with sacrifices and incense to deal with a devil. A single guardian monster or cult might be here

9 Huge salt cavern with giant crystal and desiccated corpses. Holy symbols radiate light in the vaulted ceiling. In the bottom of a vast pit is a bound greater devil. Magical wards keep evil out so devils and cultists come here to try and pass. A guardian may be here, possibly fighting the diabolical forces. The bindings of the devil in the pit require four cursed locks to be opened

10 A great bronze gate bound by giant chains held by a magic-sealed lock. Guardian gorgons, minotaurs and gargoyles defend the gate to hell this side; the other side has devils. Fountains of blood and unholy water shaped like devils decorate the room lit by burning braziers

11 A huge ornate hall with great summoning circles depicted on the floor and various devil sigils on the walls. Four great braziers on plinth light the room. You are quite likley to find cultists or a wizard with mercenaries here preparing to summon a devil for wishes. In a worse case they will summon a greater devil. They might have magical monster pets already. They often have cursed chests of treasure here also 

12 A huge hall with an arch at the end with a huge mural of Hell. By sacrificing a victim at a shrine touched in a corner the mural becomes a gate for ten minutes and wandering monsters of hell will enter and try to seize victims to open the gate longer. Damaging the altar shuts the portal. More powerful beings come if the gate is open fot 30 minutes 

There will be a second series adding details to this one