Abandoned Mines above the Caverns: Procedural Tiny Dungeon Generator 2

Below is a generator for some small dungeons which can be used to construct abandoned mines as well as cavern complexes. These will result in less treasure than most dungeons but can be the source of troglodytes which may spread out from their awful homes to menace the country side. These dungeons are created procedurally and can be rolled for as the party enters them. For the Caverns, you fill the cavern table with monsters, and then roll for room contents.

Abandoned Mineshaft Complex Generator

Mines Layout

Tunnels extending out from central hub room from which the mine complex is entered.

1-3	2 Tunnels of 1d6 Rooms
4-5	3 Tunnels of 1d6+1 Rooms +  1 side path between two shortest tunnels
6	4 Tunnels of 1d6+2 Rooms + 1 side path between two longest tunnels + 1 side path between two shortest tunnels

Outermost room of the two longest tunnels will allow descent into random rooms of the caverns below

Mineshaft Room Contents 1d8 + 1d8 (Roll twice per room)

1-3	Empty 1 The shaft here is supported by numerous wooden pillars. 2 The ceiling buldges down from above, as if about to collapse inward. 3 A wheelbarrow has been abandoned here, its wheel broken. 4 A lantern lies broken here, now a cracked shell of glass. 5 Three wodden pillars have fallen from the wall here, and now lie as rubble. 6 From this wall ore was once taken, all that is left is a gaping orifice. 7  A deep hole has been dug here and a ladder leads down into it. 8 The walls here is broken, its stoney flesh littering the floor.
4-6	Trap 1-3 Unstable tunnel, rocks fall from ceiling for 1d8 damage 4-5 Tunnel Collapses and exit into room covered by stone only passage further inwards, can be removed with 2d4 manhours of labor (assuming a roll of 4 three characters and a hireling could remove the stones in 1 hour and one character in 4 hours) 6-7 Collapsing floor into random room of caverns below, fall deals 2d6 damage 8 Blackdamp - Open flames snuff out while encased lanterns dim further there is a 1 in 6 chance of a damp requiring a save vs poison or unconciousness and death if they remain in that area
7	Monster 1-4 Crazed Miner who has been trapped here some time ago  (Stats as bandit with 2 HD and undead morale) 5-7 Swarm of Bats  (flees after taking 1 hp but is able to attack entire party at once for 1 hp) 8 Monster from Caverns Below
8	Treasure 1-3 1d10 nodules exposed of precious ore  each worth 1d6*10 silver and requires 1d6 turns to remove all 4-6 1d6 nodules of exposed gems  each worth 1d4*20 silver  and requires 1d6 turns to remove all 7 1d8 nodules of mined precious ore  each worth 1d6*10 silver 8 1d4 mined gems  each worth 1d4*20 silver

Wandering Monsters 1d8

1-4	Crazed Miner
5-7	Swarm of Bats
8	Monster from Caverns Below

Caverns Below Generator

Rooms: 2d6+Number of Tunnels Above

Cavern Layout*

1-3	Two linear rows of equal rooms connected to each other by  sidepaths equal to number of tunnels above
4-5	Two floors and two staircases that connect between them.  Top has number equal to tunnels+1d6.  Bottom has the other 1d6
6	Many floors each has number of rooms  equal to number of tunnels above

*To construct a Larger Cavern, simply fill the mineshaft columns above with cavern room contents

Cavern Room Contents 1d6 + 1d6 (Roll twice per room)

1-4	Empty 1 A massive pool of water covers the majority of this cave. 2 Numerous stalactites hang from the ceiling above. 3 The roof of the cave hangs low limiting your ability to stand tall. 4 The cave here is barely wide enough to walk through. 5 Water falls from a ledge above. 6 The cave winds about instead of being easily visible and understandable.
5	Monster* 1  Lesser Inhabitants 1st roll 2  Lesser Inhabitants 2nd roll 3 Lesser Inhabitants 3rd roll 4 Greater Inhabitants 1st roll 5 Greater Inhabitants 2nd roll 6 Terrible Inhabitants
6	Treasure 1-3 Fossils embedded in the wall  worth 1d8 * 50, each 100 silver corresponds to 1 encumbering item requires 1d8 turns to remove from wall 4-5  Exit out of the cavern 6 Strange Protohuman Relic carved from pale stone  worth 2d6*30 silver

Wandering Monsters* (1d4)

1	Lesser Inhabitants 1st roll
2	Lesser Inhabitants 2nd roll
3	Lesser Inhabitants 3rd roll
4	Greater Inhabitants 1st roll

*Determination of Cavern Inhabitants

Lesser 1d8 

(Stastics unless specified as different are 1 HD, Armor as shield, 1d6 damage, movement as unencumberd man, average morale)

1	2d4 Armored Trilobytes crawling out of a stagant pool of water (armor as chain and shield)
2	1d4 Giant Bats unfurling their wings from the cavern's roof  (2 HD, low morale)
3	1d2 Cave-Fishers reeling themselves towards their filaments (attack from range and if successful embeds filament strand within target)
4	1d6 Claw Shrimp floating up form the water below (Two Claw Attacks for 1d6)
5	1d3 Giant Centipede spiraling downward from stalagtites (Attacks with poison, high morale)
6	Stone Mimic silently ambushing as it opens its eye  (surprises on 5 in 6, and morale as undead)
7	1d2 Snapping Slamanders swimming out of some submerged hole (On hit pulls target into water, dealing 1d6 every round)
8	1d4 Opilions converging along the walls (Crawls on wall, if fails morale plays as dead)

Greater 1d6 

(Stastics unless specified as different are 3 HD, Armor as shield+leather, 1d8 damage, movement as unencumberd man, high morale)

1-3	Double number of appearing Lesser inhabitants
4	1d2 Serpent Bats screeching and flapping their awful wings from above (Attacks ignore shields, Movement as double that of unencumbered man)
5	1d3 White Apes howling and  as they feast on the corpse of a  (Roll again for monster) (No reaction roll are always hostile)
6	Scythe Trilobyte lunging a blade out of a pool of water  (Armor as Plate + shield, 2d6/2d6 damage)

Terrible 1d4

1	Double number of appearing Greater inhabitants
2	Terror Mole bursting forth from the walls of the cavern  (as Troll with burrowing speed equal to man in plate)
3	Banished Jotun thrashing and screaming out of chains and shackles  (as Hill Giant but half movement)

Bonus: FANTASTIC DUNGEON DENIZENS

The following can be applied separately or in tandem to make the caverns inhabitants more fantastic

Sentient Creepy Crawlies:
Each Lesser and Greater Inhabitant has a 1 in 6 chance of being sentient and being able to speak.

Cave-dwelling men dressed in creepy crawly skin:
Each Lesser Inhabitant has a 1 in 6 chance of a man dressed in leather/chitin (Stats as bandit + modifications of inhabitant) One Cavern room has secret entrance to small hamlet at bottom of cave.

Troglodytes:
Each Lesser Inhabitant has a 1 in 6 chance of being a demi-human race (Stats as lesser inhabitant with Double HD) One Cavern room has secret entrance to small village at bottom of cave.

Goal of Procedures

Procedural generation of mines and caverns beneath. Alot of inspiration was taken from the film The Descent and a mechanical incentive of "we have to go lower to escape" was emphasized. For this reason a treasure listed within the caverns is an exit from the dungeon which has a slightly greater than 12% chance of appearing within a room. With an average of 7 rooms within a cavern (not counting the additional rooms from the tunnel) this means that there is a 64% chance of the average caverns below having at least one exit out of the mines. There is a 9% chance of a mine shaft being collapsable which has a 2 in 6 chance (trap chance) of triggering per party member who travels through it. Assuming a party of 4 PC's and 2 hirelings there's a 91% chance of that party triggering a collapse of stone behind them which means they would have to either go deeper into the mine to search for a way out. Further each room has a 9% chance of being trapped to collapse downwards into the caverns. Assuming the previous party there is a 91% chance that one of them collapses downwards into the caverns and as there is a 64% chance of the caverns having a secondary exit there is only a 34% chance a party would have to travel upwards to exit the mines. The mines contents were weight towards being filled with traps rather than monsters and the caverns below infact are the opposite and have no traps. This was to create two states of the complex with the abandoned mines being desolate and the caverns teeming with life but both would still pose a threat to those who would explore.

The mines and caverns are further filled with treasure which is weighted to be produced as within the walls of the mine instead of on the floor. The intent here is to create reasons to return to the dungeon at a later date with hirelings and pickaxes to excavate it. The different value of gems and ores within a dungeon are randomized so that multiple dungeons could be created differently. Thus a referee could create a mine for iron or gold and have their contents feel different for the players. The creatures within the caverns (without modifications to make them more fantastic) are constructed to have a variety of different inhabitants which would change per cavern complex. This would allow multiple cavern complex to feel different from one another lest each cavern complex encountered would have the same trogodyte denizens. Lastly the stats of the denizens are arranged in such a way that the fantastic elements could be easily consturcted. For instance the cave folk who wear the chitin of trilobytes would be better armored and the demihuman centipede folk would be easily made rather than intricately written out.

Playtesting and Adjustments

I have run three sessions of exploring such abandoned mine sites. The only significant change from the initial draft was to reduce the amount of lethal blackdamp found in dungeons to facilitate movement downwards into the caves below. The players reactions to the valuable nodes of gem and ores as well as the fossils embedded in the walls of the dungeon was to fomulate plans to return and excavate them later instead of recovering them during the first dungeon expedition. The abandoned mines greatly reward cautious exploration and preperation beforehand as the danger of avoidable traps is much greater than that of monsters.