A d100 list of found objects, unexpected sights, and strange encounters for your players to discover while venturing through unexplored, solution-carved caves.
The steady drip of acidic water echoes through vaulted caverns.
Some caves can form in complete darkness. When water or snow mixes with organic compounds it creates a natural carbonic acid that can easily dissolve soluble rocks; such as limestone, chalk, dolomite, gypsum, marble, and salt. When this acid finds its way into splits and ruptures in the surface, it sits and slowly dissolves the stone. Eventually, this solution forms massive caverns, sinkholes, and underground drainage systems. While falling rainwater is the most common way for water to fill these caverns, sometimes the water can rise up from deep within the earth to form caves. Ones formed in this manner have higher levels of sulfur and a stronger acid.
Solutional or karst caverns are often filled with a variety of speleothems due to the process of their formation. Flowstones, stalagmites, and stalactites are created by the carbonic acid entering through a cave’s ceiling. Solutional caves are littered with strange, awe-inspiring rock formations; often resembling cathedrals of stone. Player characters won’t be the only ones to find inspiration in the depths. Numerous Underdark denizens and monsters view the formations as signs of their deities, making them important cultural and religious sites. Any parties entering these caves should expect to confront offended and fantatical resistance.
When using this list, feel free to choose any options you particularly like. You can also let fate decide and roll a d100. Every fifth option in the list is more consequential than the rest, so roll a d20 and multiply by 5 if you want to ensure a truly unique encounter for your party.
1. A rock shaped like a skull. A bat is sleeping inside the eyehole.
2. A knife fashioned from bone.
3. A stalactite crashes to the floor behind the party.
4. A sack hangs from a rope fixed to the ceiling. Inside are a bunch of fresh onions.
5. A small, glowing red crystal is imbedded in the wall. It hums faintly with energy. Any character that removes the crystal from the wall is afflicted with a blood curse. They take half of the damage they deal while carrying the crystal.
6. The remains of a burned-out campfire. A burnt corpse lies on top of it.
7. A kaleidoscope. Inside are a number of valuable crystals that produce the effect.
8. A very large mushroom cap that has grown from the corpse of a goblin.
9. A bottle filled with teeth. They look to have come from several different humanoid races.
10. [Encounter] The party stumbles upon a chimera’s lair. It is feeling in a generous mood though and might spare the adventurers if they offer valuable treasure.
11. A broken spear lodged in a crack in the stone wall.
12. A gust of wind blows through a crevice in the ceiling. It makes a sound resembling a ghostly wail.
13. A cluster of deep purple flowers. They smell like honey.
14. An eroded stalagmite. It resembles a humanoid wearing a long, hooded cloak.
15. Three dwarven spelunkers have made camp here. They are in search of an ancient dwarven king’s tomb. They have some exploration items and food that they can trade with the party.
16. A cavern covered in spotted fungi. They look like ordinary mushrooms under light, but glow brightly in complete darkness.
17. The walls seem to shimmer for a second, almost as if they are illusions.
18. One party members gets the sensation of being watched. They spot a pair of yellow eyes in the dark, which then vanish.
19. A broken oil lantern. It is still usable but consumes twice as much oil over due to a leak.
20. [Encounter] An irritable ettin. One of its heads is a bloodthursty bully and the other is an aspiring pacifist.
21. An old letter, spotted with stains and dirt. It appears to be the romantic rejection of a love interest.
22. A rusty greatsword missing half of its hilt.
23. One member of the party begins seeing spots as if they had been staring into the sun for too long. They disappear after a minute.
24. A knapsack with surprisingly fresh pastries and a half-finished bottle of wine.
25. [Encounter] A group of reformed gnolls. They’ve managed to build a small community in this cavern and claim to have given up their marauding ways. Though some of the nastier looking gnolls keep hungry eyes on the party.
26. A library. Shelves filled with dozens of books have been cut into the stone walls. However, each book is blank.
27. Acidic water covers the floor of the cavern. Bubbles occasionally rise to the surface, carrying a sulfuric scent.
28. A dismembered arm has been pinned to a stone. Its finger points back down the tunnel from which the party just came.
29. A limestone statue resembling an Underdark goddess.
30. A pool of bright pink liquid. It is held in the concave bowl of a raised rock pillar. Drinking it cures all negative conditions.
31. A shrunken, dried thumb in a glass vial.
32. What appear to be bushes. On closer inspection, they are large helictite formations.
33. The echo of a drum. It beats faster and faster for a minute before stopping altogether.
34. A tin box containing a cloth doll. It has needles stabbed through both of its eyes.
35. [Encounter] This cavern is filled with stalactites, stalagmites, soda straws, and other speleothems. Unfortunately for the party, there is also a mimic disguising itself as one of these rock formations.
36. A lizard with another head instead of a tail.
37. Stalagmites and stalactites that all resemble large, humanoid fingers cover the floor and ceiling.
38. A rectangular door is set in the wall. Behind it is a small storeroom with only a broom and spiderwebs inside.
39. A tattered scarf clutched in a skeleton hand.
40. A crystal chair sits on a short, stone dais. Resting on the chair is an archaic tome. Whoever opens the tome and reads through it recovers spell slots and ability slots as if they had taken a long rest. The tome then disintegrates. The character who read it is unable to remember anything they read afterwards.
41. A pillar of solid bloodstone. It seems to absorb light.
42. The sound of footsteps approaching quickly from behind the party. It continues past the party and farther down the tunnel.
43. A sword made of pure glass. It is beautiful but won’t hold up under real use.
44. A spider falls onto a party member’s shoulder and whispers “don’t look back” before skittering away.
45. [Encounter] The floor is covered in a thin layer of water here. Lurking underneath the surface is a black pudding.
46. A slightly dented horn. Dry blood is caked around the mouthpiece.
47. Purple glowworms hang from the ceiling.
48. An empty wine bottle. It has become a terrarium with a mini forest of moss and fungi inside.
49. An altar to an unknown god. A rune has been scrawled onto it in fresh blood.
50 [Encounter] A group of slaves mining limestone. They are overseen by a party of drow and driders.
51. A cooking pan. Scrawled into the wooden handle is the name “Biggs”.
52. Ten candles form a small ring around a stalagmite. Two of them are lit.
53. The skeleton of a young dragon. It is unclear how it died.
54. A shallow wooden bowl holding a pale, milky liquid.
55. A small drum with a pair of humanoid rib bones resting beside it. The drum makes no sound unless struck by the bones. If separated, the bones will magically appear next to drum after a full day.
56. A field of red-purple grass covers the floor. The blades make a loud cracking sound when stepped on.
57. The tunnel continues at a steep downward slope for the next mile. The rock underfoot is very, very slick.
58. A vein of precious opal in the cavern ceiling. Of course, the ceiling is 45-feet-high here, so mining it won’t be easy.
59. A glass eye. It is far too large to belong to a humanoid. It is also frighteningly realistic…
60. [Encounter] A foul stench fills the cavern. Squatting over a pile of bones is the source of the stench – a hungry ghast.
61. A massive helictite resembling a stone tree hangs from the ceiling.
62. The walls are covered in tally marks. Thousands of them.
63. A small crystal. It appears to have a cavity inside which is currently filled with dark red blood.
64. The sound of a rainstorm fills the cavern. Despite this, the air feels dry, and the water level remains the same.
65. A pair of holes in the stone wall that have a slightly tapered, oval shape. They are perfectly spaced for a character to peek through both at the same time. If any character does, they see another pair of eyes looking back before becoming blinded. The condition goes away after an hour.
66. A travelling pack with a shovel nearby. Inside of it is a bloody bedroll, a bag of coffee beans, and a locket with a picture of a dwarf woman inside.
67. A old sword has been plunged into a stone. Thorny vines grow from the rock and wrap around the blade, hilt, and pommel.
68. A pair of boots. Inside, spiders, centipedes, scorpions, and other arachnoids/insects wriggle around.
69. A humanoid skeleton rests cross-legged against a stalagmite. It holds a dagger in one bony hand and a gold coin in the other.
70. [Encounter] A pack of gricks have made their lair in this cavern. They have been without a meal for a while, but luckily the party has come along to solve their food shortage.
71. A metal pole stretches from one wall of the passageway to the next. Striking it fills the air with a metallic thrum.
72. The corpse of an albino bear. It has a large bite taken out of its side.
73. A cloth sack. Inside is the decapitated head of an ogre. Its blood has stained the bottom of the sack.
74. A statue of a benevolent deity. They are covered in strange symbols and deep gouges. An evil aura emanates from the stone figure.
75. Moss, fungi, and lichen in varying colors completely cover the floor, walls, and ceiling of this part of the cavern. A sweet scent fills the air and gives the party a sense of safety and respite. Taking a short rest in this area grants the benefits of a long rest.
76. A pile of thick, yellow-green sludge runs down one of the walls. It smells of rotten eggs.
77. A dead goblin. Well, the top half of a dead goblin.
78. Dark blue mushrooms grow on the ceiling. They emit spores that stick to the characters and glow a soft yellow.
79. A lifelike statue of a young human. Their face is twisted in horror and they appear to be reaching for something.
80. [Encounter] The putrid stench of sulfur and death fills the chamber. This cavern looks to be a troll lair, but there are no trolls here now. There is however a carrion crawler that has been hanging around and sneaking some of the troll’s leftovers.
81. A satchel wrapped around a stalagmite. Inside is a glass jar with a dead butterfly and a rusty fork.
82. A glass orb with a stopper. It is filled with pungent mead.
83. A page torn from a book. It is impossible to tell what the original text said, as someone has scribbled the word “garble” over it repeatedly.
84. Arrows have been scratched into the cave floor. They point back the way the party came.
85. A skull hanging from a metal chain. Its eyes glow with a green light. Characters that look deeply into the eyes can see images of lost loved ones and companions.
86. Stagnant water covers the floor. A rat corpse floats on the surface.
87. A swarm of bats. They appear to be disfigured, with patches of fur missing and extra limbs growing out of their backs.
88. Terrified mumbling echoes through the cavern. A party member’s name can be made out amidst the mumbling before it ceases.
89. A toy horse. It is covered in mud and cobwebs.
90. The party enters a circular cavern. On a pedestal at the center is a malachite orb. When a character touches the orb, they are able to see the spirits of those who died nearby. The only current specter is the previous owner of the orb, who warns against using it.
91. A thick, solutional mist fills the cave, making it difficult to see and breathe.
92. Rows of square holes line one wall. They are arranged neatly and symmetrically. Inside of one is a child’s doll.
93. Lichen spells out the word “danger” on the floor.
94. A ceramic jug filled with mineral water. Thick algae has grown on the surface of the water.
95. [Encounter] The cavern ahead is filled with violet fungi, shriekers, gas spores, and even a myconid or two.
96. A silver ring still being worn on a severed index finger.
97. A sealed bottle filled with strawberries, raspberries, blueberries, and blackberries. They look surprisingly fresh even though the bottle is covered in dust.
98. A stone pillar. Ruts have been carved in a spiral on the ceiling and floor with the pillar at their ends, almost as if the pillar has been circling the cave.
99. A desecrated altar to a deity of darkness. One party member feels unnaturally compelled to restore it.
100. [Encounter] An old human in tattered rags. They are a stoneweaver and have lived their entire life in these tunnels. (Have fun as the DM giving them all kinds of stone-themed powers!)