d100 Flesh pits of the space gods pt1: scenery

I have alluded to fleshy tunnel complexes a few times. Some possible example include:

In a ruined section of a starship, flesh has grown, replacing starship sections with alien tissue instead of steel. Is it a mutant? An alien? A fungus? A colonial life form? A machine that has come to resemble a living thing?

When a outer god swallows you and takes it to the inside of it's body in overspace

When party have to get inside a party member to save their body from microscopic monsters

A mysterious huge cube of flesh with mucous dripping entries is found in a isolated valley

Inside the body of a sleeping kaiju
Under the temple of an elder god is the trapped body of a god
Inside the sleeping god
Inside the wale that ate your fleet
Inside a biological alien ship
In the dungeon of the meat god or a god of chaos
Inside a living Island
In the hentai dimension

Between the dungeon levels is a colossal creature maintaining the dungeon, birthing monsters, and regrowing doors and chests and treasure

So having established the need for this horror here we go. I recommend cave geomorphs but I might try designing some. This is one of those things I have always wanted.

1d10 Basic Bio-Complex Sections
1 Entry Portals
2 Flesh Tunnels
3 Fluid Transmission Tunnels
4 Digestive Tract
5 Refinery Organs
6 Defence Structure
7 Reserve Storage
8 Reproductive System
9 Habitat Organ
10 Mastermind

1d10 Basic Bio-Complex Sections
1 A great living portcullis gate with teeth, dripping with fluid opens into a huge chasm with side passages and a main transit tunnel
2 A swarm of small insectoids form into a doors or walls and back, tiny creatures make up walls, floors and ceilings reconfiguring for defence or rapid transit, some form a disguise over entry
3 A great bio gatehouse with guardian chambers above entry maw and sensory apparatus to warn them, inside is a chamber with a second defencive gatehouse then a hub that breaks into more sections
4 A great sphincter of muscle requires special attention to open, corridors may constrict, spasm or be covered in phlegm
5 A fleshy hole with bristles and toxic secretions keep away outsiders, mites and guardians might guard too, usually not too visible from a distance, distant sounds echo inside with various large round chambers and spiralling corridors
6 A great flap of tissue opens to vent gas and waste, inside is a wet tunnel with strong air currents spiralling into the section into a great hub of smaller tunnels
7 A great stinking pit with great bristles where waste products are vented. A series of foul chambers of rotten matter with tunnels twisting into the interior
8 A great chamber mouth with great fibrous filter plates inside opening. Intruders can slip through when gate mouth opens, horrible shrimp like lice live in the fibres and attack intruders that smell wrong
9 A great dripping fleshy pit with a coloured pool is a barrier to open spaces inside and may clench shut to keep out danger, opens for native fauna who bring input like food to system here
10 A cocoon like gate way splits open in middle into pie slice triangles to admit beings. An eye or many more on tendrils or on door identifies friendly beings to admit
11 Dry skin like walls with bristles and strong air currents blow through here sometimes with aerosolised fluid or biological culture simulating local weather. Tunnels may flex slightly or have pressure changes indicating change on way
12 Squirming tentacle lined corridors, often slimy and possible hostile if system able to respond bu=y usually tasting intruders but may also carry welcome passengers through system
13 Quivering tight flesh found corridor, hard to stand on as moves and contracts when disturbed or touched. Air moves rapidly with harsh internal weather. Occasionally a high pressure shock wave blasts through but more often just coughing slime or intruder through system. Can be very dangerous and may rupture intruder eardrums
14 Huge variegated plates of metallic chitin in geometric configurations might appear to be alien craft but is living. Articulated claws, and eye stalks  guard doorways of chitin armoured flesh
15 Gelatinous quivering slippery slimy tunnels, may sink up to ankles, knees, waste or deeper, some areas more like a moving river of slow flowing ooze
16 Bone like shape structures with with skin over frame, walls are metallic bone under leather feel surface. Great valve doors seal sections. Cold and stark mostly but some warm, even fur covered.
17 Scaled plates and curved structures, ridged corrugation with tubes and pipes running over all surfaces. Regular access ports interface with other sections, scales forming an iris valve door
18 Limestone calcium like caverns dripping with fluids and even life forms, hidden chambers, under fluid chambers, occasional fleshy doors or secret moving walls hide rooms
19 Slimy stringy threads cover surface of tunnels that seem to be made from a mass of fibres,  often cramped with damages sections with broken bundles and threads hanging down blocking views. Creatures easily squeeze inside the walls and use to ambush or hide
20 Rigid fleshy surface with regular sucker cups like octopus tentacles or some other fleshy structure with cloaca doorways and vent openings, some dry others more mobile and protrusions move and may even have a stream of fluid flowing through it
21 High Pressure doorways into round drains where high pressure fluids flood through. Some flow constantly others more intermittent and tend to run in parallel. Opening wrong door makes some fluid burst out flooding an area before wall and tunnels close
22 A huge rhythmic pulse of mighty heart like pump or multiple pumps working all sorts of fluids through system, area spasms with every beat as titanic organs pulse
23 Huge cavern with a porous filtration reef with a rich ecology to clean systems liquids
24 Huge floating tree shaped structures immersed in liquid cells further cleansing system fluids, creatures here feeding
25 Chambers with canals throughout with rich flora and fauna and goods transported in biological pods like barrels or bigger
26 A huge chamber with water storage and an ecology of large docile filter feeder and some other creatures in a slow paces area
27 Great drain way always full with strong current and some fast predator antibodies
28 Great drain way empty mostly, a back up with many tunnels and hubs, unwelcome squatters
29 Great chasm lake with polluted foul liquids, mostly quiet
30 Great lake with remnants of things consumed long ago, survivors somehow survive in community
31 Sponge geometric tissue lined cavern, dripping with chemicals, many dormant, most empty but sometimes past food preserved in gelatinous slabs. Living creatures might live here or be awakened as system reanimates. Prone to seasonal chem floods, quakes, gas but mostly kinda clean
32 Huge caverns of flesh, tight with gas bubbling up from covered chemical lake producing nutrient for the greater body from raw materials. Quakes may make floor unstable and ripple or tear like a swimming pool cover over an acid lake
33 Caverns of tiny creatures crawling and swarming and gnawing and dismembering trash or corpses. When full they creep into mouths set around walls. New bugs hatch from mounds of eggs by workers
34 Huge vats of sweet liquids are stirred in giant bio vats then shaped into novelty pellets and structures for storage, unwelcome creatures chased away by guards. Sugar crystal barges transport selves and goods to other feeding areas
35 Giant caterpillars grazing on fungus happily like cows, hunter predators come to feed off the crying dumb beasts and occasionally stampede, actually this party of ecology transmits nutrient around system
36 Insectoid creatures chew on foodstuff then store in hive cells where it refines over time with their saliva into a superfood. Guards protect the honey from thieves, some have additional properties much sought after
37 Huge insects or grubs graze on fungus their huge abdomens filled with fluid other smaller creatures milk and transport to other creatures in the system, trails of tiny bugs follow each colossal grazer with some carrying huge sticky droplets for delivery
38 Radioactives refinery of glowing pods connected by pipes that make up most of the walls and ceilings. Many pipes hold high pressure radioactive fluid or steam and are dangerous to breach. Bulkhead doors seal compartments and speciality armoured denizens transport dangerous materials
39 This area is filled with specialised hibernation pods where data is extracted from living brains of outsiders. Each jar holds a prisoner which neural tendrils attach themselves to the creature for life support and to form a brain link. Data DNA and memory RNA is duplicated, refined into a cylinder of fluid and taken to the system brains for study. Useful beings get stored in best condition, other keep only heads or brains
40 A biological foundry with hot humid air, huge pumping bellows, chemical and thermal furnaces, rending metals and more resilient materials into fuel or building materials, workers scurry about but might try to use materials here as weapons if threat detected
41 A huge cavern with a fermenting lake of biological agents producing nutrient for the system, other creatures lurk inside and great fleshy pseudopod stir the lake
42 Round tunnel, warm to touch, feel skin tighten beneath your feet but
43 Series of chambers and tunnels is a organic factory for grinding and shredding materials before chemical processing. Often not functioning and dormant but when alive begins to try moving into serrated grinding ridges on roof and ceiling sides. Floor like a muscular conveyor belt and lubricating fluids flow into corridors
44 Cavern dripping with thick fluid with gelatinous creatures hungrily breaking down creatures that have been consumed or wandered in here, a few creatures still live and wander hopelessly seeking escape
45 A huge chasm or series of chasms with a great lake and veins and curtain like ridges growing over the dome ceiling. Consumed things may be in here and an ecology of organisms and parasites
46 Canal with thick gelatin rivers crawling with slime creatures and antibody defenders, squirming with translucent life forms
47 Rivers and pools of foamed eggs and frogspawn flowing through caverns being assessed for deviation and contaminants removed before being grown into different beings elsewhere
48 A cavern system heaped with garbage and trash, fermenting away with creatures and parasites crawling everywhere with recycled system fragments and other things in rotten mounds. Some areas more flooded, some creatures build dams and rafts from scraps
49 Winding caves full of highly refined grades of sticky toxic scum, nasty and roaming with creatures, flammable gas and stinking clouds common
50 Squirming folds of flesh with rotten matter, crawling with worms and other creatures
51 Biological gate station with murder holes in ceilings of toxins or corrosives, guards sweep through after to mop up any survivors
52 Barracks with hundreds of troop creatures hanging from rails, in pods if for long term storage
53 Bio armoury where creatures designed and grown for use as weapons, bioguns shoot living ammo or heavy weapons that walk and are guided by troops to position. Specialist brains in sealed section develop new weapons to respond to intruders
54 Defencive fort to guard a section can be flooded with gas and contains troops. Bulk of troops remain inside and shoot intruders through slots on surfaces. Many dead end traps with huge valve doors
55 Swarm drone hangers where scouts and harvester and even some war drones live in between missions outside. Often dedicated to flyers. Often long term storage ones have cocoon pods for inhabitants
56 Prison cell for interesting prisoners to have brains extracted or bodies studies. Also contain defective units for recycling and possibly remains of an old queen or young rivals to the system's dominant mind. Also keep prisoners of rival systems and defeated colonies
57 A great fortress filled with horrors for war
58 Gladiator arena where prisoners tested against system weapons and warrior drones and for war games
59 Colony of outsiders really a fake infiltrator training ground full of spy and decoy drones, various hives have different degrees of success at this task, some may be so deep they don't know they are bugs
60 Experimental weapons division where brains and smarter troop types experiment with outsider powers and abilities to turn against them, human examples might captured might be here as well as the alien versions. Here is where psionic or magical or even solid state human tech is developed and weaponized. Alien versions might include fluid in tubes, symbiotic hive swarms or other strange form
61 Gelatinous lake with stored nutrient, parasites try to steal and defender organisms hunt them and other intruders
62 Huge vats of embryos in stasis of system ecology creatures. Guardians protect them
63 Chasms with rows of biological cell pods where creatures are stored  for reserves
64 Stowage of chemicals in huge sacks of gelatinous silos
65 Stowage of raw materials like calcium and metal in hexagonal ingots in huge stacks
66 Reserve biomass for repair and building projects
67 Biomedical tissue in hexagonal cells with repair creatures monitoring system to respond to damage
68 Garbage and remains of outsiders stowed for analysts and possible duplication, encased in slime inside skins
69 Corpses of local system fauna, parasites and outsiders stored for recycling in liquid stowed in vats
70 Chasm with chemicals locked in crystalline form, a forest of crystalline tree like structures different colours for different chemicals
71 Egg chamber with egg tubes laying eggs on an assembly line with some chambers dedicated to manipulating embryos in eggs with chemicals and surgery
72 Incubation chambers where eggs bathed in radiation and various frequency EM spectrum in crystal chambers, moved by workers to hatchery
73 Hatchery where workers care for new organisms and take them to first feeding chambers for special diets to prepare them for roles
74 Reproduction vats where larger more sophisticated beings grown in huge pools with fleshy walls with umbilical cords feeding foetal creature
75 Brooder hives where creatures raised to maturity, millions of meeping creatures hungry for next feeding, fleshy pens with globes of light and heat from ceilings and rivulets of water and food pellets dispensed from orifices
76 Tight flesh globes in giant grape like clusters crawling with neotant life forms actually preserve DNA of system components, defenders very protective
77 Huge brood caterpillar like grubs lay eggs and birth creatures which are quickly carried away by nurse creatures
78 Whale like creatures in vats brood mares to all kind of creatures that swim free to fluid transport tubes to right sections
79 Fungous cavern filled with spores where fungal mounds grow into many forms and functions
80 Rigid pods packed with eggs or DNA samples, piled in huge heaps in cavern sorted by nurse creatures and some taken to hatcheries
81 Gigantic hive full of cells where creatures rest and are fed, some in long term hibernation
82 Huge termite mound like hive with thousands of workers resting and eating before setting off to work
83 Huge cavern with thousands of caves where creatures lair, some sealed and hibernating behind cocoon like barriers
84 Huge caverns with caterpillar titans with other creatures living inside them in orifices which also feed them
85 A camp of lost explorers may be friendly and join forces or try to rob and kill party, possibly cultists or under system control
86 A desperate castaway or lost explorer living in a shack built in quiet section has learnt to survive here
87 A human settlement where infiltrator creatures practise being human before fieldwork, many so deep don't know the truth
88 A ramshackle town built of rubbish and garbage where feral inhabitants have learnt to liver
89 A sealed metal bunker base or tower of someone hiding here who does not wish to be seen
90 A ruin or crashed craft of some other species with desperate survivors living inside
91 Pools in flesh cavern floor with floating brains, guardians on prowl for intruders and possible aged retired guards act as communicators with brains will
92 Great brain citadel with swarms of creatures managing the brain and sending messages to body subsystems, beings may even be sentient and self aware or even control the great brain but others are mindless component drones
93 Great cluster of nerve pylons crackling with energy transmitting commands to subsystems and controlling alarm systems
94 Great chamber with huge pillars growing clusters of brains, atendants pick them and plant in sections needing fresh neural control nodes
95 A great brain with neural threads in every directions, guardian arachnids climb on threads and spin new ones and weaves others into webs
96 Great vats cover chambers with fluid and brains inside. Some like above ground pools, others in pillars reaching to the ceiling Guardians patrol them and tend them till the grow bigger and need moving to a bigger tank
97 A great brain queen brood mother all brain and egg production responds to system needs and creates egg types required to be hatched or stored elsewhere, queen may be hostile or willing to communicate
98 Sealed pods with captured brains from many captives. The master brain here has mastered many languages and communication skills and is curious about strangers talking with them to assess if they should be added to collection.
99 Roaming tentacled brains crawl around a damp fleshy maze exchanging data by rubbing and fondling each other. Strangers will get similar treatment but disturbing routine sends area into panic and chaos. Security then called in to eliminate threat
100 Mastermind chambers where creatures record data chemically in fluids to feed to brains, some areas are labs others more like libraries where brain beasts come to feed and swap ideas. Eventually they wander off to implant selves in walls where needed. Some areas specialize in analyzing outsiders goods or cultures

d12 Luminescence
1 Dark and tries to douse lighting and responds with hostility
2 Totally dark
3 Some luminescent organisms and organs
4 Dim bio luminescence
5 Luminescent swarms move about and attracted to light
6 Weak lighting cells, flicker
7 Weak lighting cells, day night cycle
8 Weak lighting cells, lights up where heat or motion change
9 Good lighting, flicker
10 Good lighting, day night cycle
11 Good lighting, lights up where heat or motion change
12 Very good lighting

d12 System Health
1 Sick desperate for resources
2 Dying seeks to reproduce or regrow again
3 Dormant awaiting to revive or respond to damage
4 Awakening or shutting down, system slow and mostly inert
5 System operational and operating normally
6 System ok a bit buggy at the moment, immune system sluggish
7 Parasite species infest system in many niches
8 Parasite influencing system
9 Symbiote living in system taken on protective role
10 Outsiders have a settlement hidden inside
11 Colonisation mode ready to divide colony
12 Hyper aggressive in war mode

12 Point DoomTrack
1-3 System ignores intruders mostly 1in12 encounter per day
4-6 Security anti bodies start to look for trouble 1in12 encounter per hour
7-9 Tailer maid hunters come after molecular trail, security drones increase 1in12 encounter per 10 minute turn
10-11 May attempt communications, start war production scales
12 Non essential systems shut down, sections sealed while army sweeps everywhere systematicly
13+ System will seal systems and start reconfigering whole system to stopping intruder, even jettisoning or destroying or reabsorbing a section

Start at 1
+1 First patrol killed
+1 Third patrol killed
+1 Tenth patrol killed
+1 Quarantine or sterile area breached (reproduction, brain)
+1 Military force defeated
+1 First very large creature killed
+1 Sub system brain damaged or attacked
+1 Babies or reproductive systems damaged
+1 Any action causing section damage needing repair drones
+1 Any action causing section to shut down
+1 Any explosions, detonations of damaging fires
+1 First wall or door breached
+1 Third wall or door breached
+1 Tenth wall or door breached
-1 Disguise scents with local material or covering self in native gore
-1 Infect self with local parasites that mask you
-2 help or save babies
-1 kill a hostile organism like a parasite infestation in the system
-1 Manipulate local alarm nerve cluster to wind back distress levals
-1 Assist a native creature
-3 Temporary truce with organism
-5 Symbiosis pact with organism