Who Built the Dungeon and Why?

Who Built the Dungeon and Why?
Roll again if more history needed till generate satisfactory origin. Could have different builders for various levels from different times especially as pierces strata of earth left in different epochs.

D100 Who built this and why?

1 Crazed wizard built as a study, school and headquarters
2 Thieves guild built as lair, cache and for hideout
3 Military base built as fortress, supply depot or secret base
4 Holy site to contain holy books, relics and cult secrets
5 Library where books were stored for safety in ancient times
6 Humanoids and goblinkin for systematic invasion
7 Built by kobolds as homeland base
8 Dwarves built long ago as a treasure vault and fortress
9 Gnomes built as a workshop and outpost
10 Dark elves built as base for spies and training armies
11 Slavers built as a prison and workshop
12 Other planar beings built and have attracted monsters
13 Was on surface long ago and buried in mudslide or volcanic ash or sand
14 Built below long fallen surface ruins long ago but recently restored
15 A sentient self aware dungeon dimension is intruding on your world
16 A god or their followers built the complex as a test or punishment
17 Excavated by treasure hunters then finished by new residents expanding lair
18 Adventurers cleaned and expanded ruin then abandoned
19 Built as funeral complex and long stripped of burials
20 Remnants of prehuman civilisation or lost race
21 Built around crashed chariot of the gods fallen from sky
22 Humanoids built for reproduction
23 Cult built for forbidden vice and hedonism
24 Secret society made to stage revolt
25 Appeared fully formed at whim of chaos or trickster god one day
26 Built by beings at command of evil warlord
27 Secret military base for war that never happened
28 Underworld gods used as gateway long ago
29 Ancient dungeon refurbished by empire
30 Kobolds built from a kit they found
31 Built by undead for necromancer warlord 
32 Built by elementalist magician cult
33 Built as a prison complex by empire or a cult
34 Built as prison by mean ruler then abandoned
35 Built as secret utopian colony
36 Built as a vault or bunker to survive apocalypse
37 Automatons built then dissembled selves
38 Built by animals for some inexplicable reason
39 Grew overnight from meteor or volcanic vent
40 Water body moved revealing long lost predeluvian ruin
41 Built by a madman or monster wish
42 Artefact compelled savages to build dungeon to house it
43 Was a cave system originality
44 A great beast corpse rotted away left a cavity
45 Was a mine in ancient times then miners driven out
46 Child gods built for game like an ant farm
47 Dungeon grew from magic beans
48 Built at dawn of time as a gate to other worlds
49 Built as a museum or menagerie by mad wizard
50 Built by strange spirit folk from skychariot who long ago died out
51 Smuggling operation began building secret storehouse
52 Star fell here and complex built on top to hide secrets
52 Private dungeon stormers built to hide money from taxman

53 Built to breed a type of monster

54 Dungeon came from another world as part of invasion thousands of years ago

55 Dungeon built as secret prison for family of a mad king

56 Built as a menagerie by association of eccentric nobles but left to go feral

57 Kobolds just built it by instinct guided by dreams, happens all the time

58 Built as secret brewery to avoid tariffs

59 Cult built to isolate and brainwash victims

60 Was a training school for secret police and spies bu forgotten in regime change

61 Wizard was testing if they could build a complex using spells

62 Gods built it to test mortals and bet on the outcome

63 Began as a living evil treasure vault that grew and lured in monsters

64 Fortress buried in mudslide long ago and forgotten

65 Temple for a evil cult to take over a country

66 Gnomes built for a client who never paid and was abandoned

67 Goblins made it intending to link to other dungeons in failed scheme

68 Assassins guild made as a test but the guild was all killed by the law 

69 An order of knights built as secret armoury, prison, vault and record storage

70 Once underwater was made by fishmen as a temple

71 Witches had charmed slaves build it for secret rites

72 Cult leader had demons build it in return for sacrifices

73 Rock eating creature burrowed here long ago then refitted by humanoids

74 Paranoid ruler hid here from enemies assassins and his kin

75 Halflings built a underground town but goblins came and ate them and refitted it

76 Started as a basement under a ruin and expanded slowly over generations of monsters

77 Necromancy cult built to process undead in secret

78 Was a holy reliquary but fell to chaos long ago

79 Was a underground temple complex for a forgotten deity

80 Was built by a forgotten pre human race lost in the dawn times

81 Subterranean race herded burrowing monsters here and other things settled the passages

82 Alchemists worked on a monster making lab here and abandoned it

83 A cult built a doomsday device here and dungeon is inside the surviving workings

84 Escaped creatures brought as captives from a far off land built the dungeon as a hiding place

85 A colony of madmen built it for no sane reason possibly guided by dreams

86 Ogres had a colony here long ago and other creatures took over

87 A rich madman built it so he could spy on adventurers fighting his pet monsters

88 During a past apocalypse a town build underground shelters but the town has long gone  

89 Dwarfs built the place to attract monsters planning seal and to gas them all but it never happened

90 A former religion had secret mystery initiation tunnels underground but the temple has long gone

91 A terrible burrowing chaos thing once lived here and left tunnels others have occupied

92 Before humans great glyptodons for generations burrowed here leaving a network of passages

93 Giant fungi tendrils grew through the area but was eaten bu giant worms leaving tunnels

94 Roots of a great tree once grew here but giants killed it and the roots rotted away leaving corridoors

95 An apprentice lost a burrowing automaton here for years leaving area riddled with tunnels

96 An earthquake swallowed a town once and the streets and sewers and building form the dungeon

97 An evil lord build many dungeons as part of a plot but was slain by heroes

98 Adventurers searched for a city of gold driving slaves to fill the area with tunnels

99 A monster lord did it as a gesture of love for his sweet heart for them to spawn o murderous horde

100 Earth elementalists had a school here which ended with rogue elementals tunneling madly everywhere