d100 Cave Trail Side Passage Follies

These are small things to encounter exploring caves isolated from where they are found. I made them for long cave treks but off a beach cliff or in any cave possible. Probably I am making more high level stuff due to current game needs.

d10 Cave Types
01 Lairs
02 Camps
03 Water
04 Fire
05 Air
06 Earth
07 Mine
08 Ruin
09 Monuments
10 Magic

d100 Cave Trail Side Passage Follies
01 A visible 1m wide side passage crack and a dripping shaft and lump visible at the end. The lump is piles of clothes, rusty equipment and possibly some treasure. A cave fisher lurks at the top of the shaft 24m up
02 Side niche with a low ceiling is filled with mounds of loose soil with some bones scattered and giant rat faeces. A large nest of giant rats live here and remains of past victims is scattered in the nests
03 Large side cave with claw scratch marks of some beast and bones scattered inside, some cave art is visible. Lair of a d4 1=albino cave bear 2=albino sabretooth 3=giant carnivorous ground sloth (may have other dug tunnels inside) 4=Small albino allosaurus, lost pet of some reptilian sleeper colony 
04 High cave roof with niches, largest has a cave not visible to the ground where a beast sits on its treasure. It reaches by flight or climbing and snatching prey below. d4 1=wyvern 2=black dragon 3=behir 4=fire lizard
05 Piles of dirt and rubble with a path around a low mound. A giant toad hides here and will gobble up the first person to cross it (or the shortest). If attacked will flee to water or dig backwards while biting and screaming. Can eat several people up to its own starting mass 
06 Hundreds of bats swarm here and the ground is covered in guano. Several giant vampire bats live above hidden among the tiny ones and rocks 12m above. If they attack the whole area is filled in confusing swarms of bats while the vampires attack and carry of victims to drain on the ceiling
07 A cluster of fungus grows here including the giant shrieking variety, and some rotting armoured humanoid remains. A deadly violet fungi lurk on top of the corpses blending into mould and toadstools until prey gets close 
08 Some metre high holes are visible, d4+4. Carnivorous giant beetles swarm out to ravenously attack any meat walking past. Humanoid remains and grug grubs in the holes
09 High above among webs a giant spider lurks and will drop a mass of net-like a web spell before dropping on a line to poison wriggling prey. Bundles of past victims are in the webs in the ceiling
10 Giant crickets gnawing on fungus will chirp noisily and avoid adventurers, but the noise calls d4 1=firelizard often semi-buried 2=ankheg giant bugs 3=giant frogs 4=bullette land shark
11 Goblin camp with a wise woman, common fungus and bug farmers and some traders with hobgoblin guards, a bugbear taskmaster with a whip and goblin dogs. A d4 pack bugs or lizards. Will hail strangers "trade or trouble?" 
12 Orcs squad led by hero orc on a dire wolf camping. On a mission for their evil wizard master seeking a rare item, the wolf will alert them to intruders
13 Degenerate cave troglodyte lizardfolk camp, stir at the smell of meat and prepare an ambush with clubs, stone axes and venomous darts, keen to eat and sacrifice to Tsathogua
14 Dark elf camp with pet spiders with pack lizards and zombie slaves, often hide in magic darkness but consider kidnapping a weak party or offer hospitality to interesting strangers. Offer strange delights, drugs and deserts of the dark fey   
15 Group of beautiful people dressed as nobles having picnic, spirit folk or spectral minions in disguise, happy to meet travellers and swap stories and news, may give a gift to charming adventurers or information
16 Dwarf merchant camp with the old dwarf boss, an alchemist advisor and a squad of warriors. Wary of trolls and goblinoids will welcome "proper" travellers 
17 Degenerate mutant scum camping here as other peoples chase them away. Swarm non-threatening travellers for food, water, medicine will grasp with their grubby hands and pickpockets
18 Cave folk clan camp, may trade but unlikely to be friends or welcome to their fire, healing their sick or gifts of food and tools will impress them enough to join them and will offer some craft goods of flint and tusk and crystal or taken from others
19 Sad grey gnomes with tools and pack lizards with ore, on mission collecting mineral samples. Wary of strangers or communicating without the master or a superior. Eat fungus gruel and yeasty blobs at camp cooked on a tiny stove
20 Strange rare race of the underland, they are shy and wary and may have strange magic that has kept them hidden or surviving so long. May recognise gifts as friendly and only speak weird ancient languages. You will probably never see their like again
21 A bubbling hot spring with mineral salt secretions formations with amazing colours, passing creatures bathe here and reptiles use to warm up and shed. 1in6 of these pools are inhabited by some encounter
22 Pool of ancient brine from the most ancient of seas buried long ago, strange shrimp creatures swim in it and salt crystals attract creatures looking for a lick of salt. Walls have pick marks from where bricks of salt have been mined here. The pool is unfathomably deep. Sometimes a black slimy blind seahag crawls out for food, ignorant of most of history she has been alone for most of the world
23 A fetid chaos tainted pool that causes minor mutations or worse, water weirds swim in it and 1in4 visits a gaggle of chaos mutants are here to worship
24 A waterfall from above fills the cave with mist, some scattered bones are on the ground and in rockpools. A few shiny trinkets can be seen in the water from past visitors. d4 1=marine troll lair 2=marine umberhulk 3=dragon 4=frog demon
25 Pool with a whirlpool, must be crossed to pass carefully, a thing lurks beneath d4 1=chaos cave octopus 2=water elemental 3=hydra 4=marine dragon 
26 A bridge of stone over a ravine with a river, a tight chokepoint for travel d4 1=orc bandits 2=
27 Sunken boggy cave with ferns and fungi, dim luminescence and fog make it seem eerie. d4 1=pack of giant frogs 2=giant beetles 3=albino crocodiles 4=agressive fungus pygmies
28 A spectacular fountain depicting gods in a high vaulted chamber. A guardian protects the water and is reborn daily anew d4 1=dragon 2=giant 3=sphynx 4=faerie noble. It keeps unworthy away from the water d4 1=healing spring 2=grants divination question 3=glowing relic in the water 4=allows you to see far away places
29 Strange coloured pools each has different strange effect, smells like chaos magic
30 Frozen cave full of blue ice, frozen things are in the ice including remains of travellers from thousands of years, inside is a lair of a d4 1=frost salamander 2=ice toad 3=cold elemental 4=ice devil
31 Hot dry cave with dedicated corpses d4 1=hellhound 2=firetoad 3=firelizard 4=fire salamander
32 Cave connected to burning coal seam, toxic smoke pours from vent and is sucked into another, dedicated smoked bodies and ash heaps are scattered about
33 Pit with bubbling lava, used by some creatures for heat, rubbish or as entry to the magma stream, d4 1=magmafolk warband 2=firebats 3=fire elemental 4=imp looking for trouble
34 A rock bridge over lava guarded, various defenders halt unworthy d4 1=bronze golem 2=fire giant 3=dragon 4=barbed devil
35 Bubbling pool of stinking sulphur d4 1=dwarf collecting chemicals 2=ochre jellies but yellow from pool 3=imps bathing d4 with a pet larvae 4=yellow dragon
36 Path through a waterfall of lava, d4=fire giant 2=red dragon 3=fire lizard 4=Firetoads
37 Great flaming pit with stairs down to bronze doors below, an efreeti with pet salamander lives here with lava folk servants. Guests with gifts get an audience
38 A pit of burning gas with crumbling ruins in the rubble in the bottom where treasure might be found d4 1=fire elemental 2=fire salamander 3=fire snakes 4=fire toads
39 Black glassy castle with lava moat inhabited by firenewts led by a knight, they have striders and fire lizard pets
40 A flowing lava river with bridge collapsed, requires repairs or jumping from rock to rock to pass
41 Great windy chasm into deep, a narrow ledge road runs alongside it
42 A great windy chasm with a bridge d4 1=gatehouse operated by gang or kingdom 2=broken and hastily repaired 3=one person flimsy rope bridge with pterodactyl abhuman nest in area 4=narrow rock bridge but creatures prey on travellers usually cloakers or cavefishers
43 Passage covered in slippery ice and with a cold wind, easily slip down to deeper depths
44 Great chasm requiring climbing to cross, giant bats swoop at intruders
45 A shaft reaching to the distant surface but a hard climb, some remains of surface creatures scattered about
46 In high ceiling of cavern is a structure wedged in rock d4 1=sailing ship 2=shattered fort 3=broken bridge 4=mass of wagons. Inside are some remains of bodies and d4 1=giant spiders 2=trolls 3=mad old hermit outcaste or survivor 4=werbats
47 A great windy pit goes up and down with a narrow walkway around the shaft, occasionally an air elemental attacks
48 Strange vapours come from a crack causing unconsciousness and otherworldly visions, if left unconscious will eventually asphyxiate. Small pets and local animals chitter when close
49 A round cave with several passages, a whirlwind circles the room and sweeps any caught up a shaft into darkness
50 Long ago an invisible stalker was set as a guard here of buried treasure, old bodies torn apart lay about
51 Chamber of delightful huge crystals with dripping water, crystal creatures hide here 
52 Chamber partly flooded by thick mud, needs to be waded through to cross 
53 Huge balanced rocks require careful climbing to cross a pit into the deep
54 A large chamber with boulders and some crushed traveller remains, living boulders and piercers lurk here 
55 A vast lake of sewerage with tentacled monsters feasting on the muck
56 A subsidence in cave splits it and one level is a serious climb to reach and is difficult to see
57 Cave of clay with a clay golem that seems to be relief art guards it against intruders, the clay has magical properties used in enchantments
58 Stone giant guards a prehistoric stone circle imprisoning a demon, cultists pilgrims come to fight the giant and free the demon bound in a buried idol in the circle
59 Broken ruins of a fort used by prehumans, strange huge broken crystals used to be some power source. Earth elementals guard the ruins and some chambers have been sealed for aeons
60 A great chamber of crystals with a huge one in the centre that drains HP of any who pass, attacking it releases several wraiths to defend it
61 Glistening minerals in walls have been gnawed by some creature, 1in6 chance xorns are here eating and they might smell tasty gems on travellers
62 Scaffolding and tracks for a minecart are here, long neglected
63 Zombie miners are working a seam for someone to collect their ore
64 Scaffolding and minecart tracks here with busy goblins busy mining, willing to trade rather than fight
65 Gnomes working to cut large crystal pillars down, wary of thieves 
66 Dwarves working a seam of ore to be shipped away by pack lizards
67 Remains of a collapsed mine entrance, if opened undead ghoul miners or out starving for flesh
68 An old mine shaft with glinting silver nuggets in the dark. Old mining equipment is scattered about, Darkstalkers within wait to ambush intruders
69 Mounds of mining rubbish and rubble and visible signs of collapsed mine tunnels. Giant ants here have been collecting gold left in a nest complex
70 Partially buried gate exposed by a recent rockslide
71 Remains of a tower here with the magical residue of the former gate here, possibly secret rooms exist
72 A giant stalactite on a high ceiling is an ancient watch post mostly hidden with chambers within. d4 1=squidfolk mentalist 2=darkstalker clan 3=fish folk cult 4=demon worshiping mutants
73 A castle on a higher level fell through a sinkhole and is mostly rubble. Buried ancient treasures ay be here under rubble
74 Ruined gatehouse of underground kingdom, often occupied. d4 1=troll  2=orc bandits 3=goblinoid gang 4=goblinoids
75 A great black crypt imprisoning an ancient evil from the dawn of time, cult pilgrims come to worship it and try to open it
76 Ruined citadel reaching into a huge chamber lit by a great light in the ceiling, remains of unknown race with some mummified remains. Their writings reveal they meddled in blasphemous lore of the outer void
77 Remains of a ruined village, a failed colony that was destroyed by a disaster 
78 A ruined fortified manor house crawling with monsters that have moved in
79 Crumbling ancient bridge with statues, entrances to chambers into the interior are visible where creatures have made lairs
80 Gates to an ancient elevator shaft used to move lots of people long ago into the deep, some have remains of mechanisms like cogs and chains
81 Dozens of shrine niches many to forgotten and lost gods, some defaced and unrecognisable
82 Huge serene sitting god relief carving with ancient script carved, enigmatic god and language unknown to the current era
83 Relief carvings and text badly smashed and faces smashed of
84 Two statues of monsters facing each other with path between them 
85 Demon statue holding stone braziers with huge cursed crystal eyes, touching them summons demon guardians and wrath of the being
86 Huge gallery of cave art depicting creatures being hunted by figures, some depictions are strange and depict unfamiliar beings
87 Huge stone statue reaches up into mist-shrouded ceiling
88 Huge statues collapsed and parts of them recognisable in huge rubble heaps
89 Gigantic stone heads, mostly non human monster kings of old
90 Squat toad demon of the outer darkness statue, if disturbed a formless guardian horror oozes from a dark well before it
91 Great stone design on chamber floor once used for gates or teleporters
92 Broken stone ring structure one used as a portal long ago
93 Cave of strange crystals producing magic null zone
94 Bubbling pool of primal chaos in a pit. Strange things crawl forth from time to time. Locals try to block it every few months but things in the pit and cultists destroy these efforts 
95 Strange glowing veins of minerals pulse here emitting rays that weaken and confuse minds
96 A magical barrier here makes a target alignment or species unable to cross without a save, stone stelae maintain the barrier and some have been damaged
97 Chamber with dozens of frightened statues where some petrifying monster like a basilisk or a gorgon lived. Long petrified beings could be revived
98 An ornate door if touched glows with magical symbols. If puzzle can be solved the lock can be opened d4 1=demon 2=petty god 3=shoggoth 4=lich  
99 Black sphinx statues (or other creatures) guard a long-unused passage. The statues shoot disintegration rays at any who try to enter 
100  A huge devil head whose mouth is a gate to hell, imps tempt passers to enter for free wishes