Thank you for all the input - I have already started to read some of your suggestions and the atlantis disney movie is scheduled to be watched the coming weekend.

Some additional ideas I had concerning my setting:

I. Plato in the Critias gives a description of Atlantis (cited from Wikipedia):
 
"Poseidon carved the mountain where his love dwelt into a palace and enclosed it with three circular moats of increasing width, varying from one to three stadia and separated by rings of land proportional in size. The Atlanteans then built bridges northward from the mountain, making a route to the rest of the island. They dug a great canal to the sea, and alongside the bridges carved tunnels into the rings of rock so that ships could pass into the city around the mountain; they carved docks from the rock walls of the moats. Every passage to the city was guarded by gates and towers, and a wall surrounded each of the city's rings. The walls were constructed of red, white and black rock quarried from the moats, and were covered with brass, tin and the precious metal orichalcum, respectively."

So, like this:


I want to develop a mechanic for explorations with a submarine in the ruins of Atlantis connected with diving expeditions. I thought of maybe using the city-crawling rules in Vornheim (maybe together with an Antlantean alphabet like this one
instead of the standard one) to create the basic layout of the ruined city combined with a hacked version of the "Instant Location"-generators found in A Red and Pleasant Land to create content for more detailed "diving-expedition-adventure-locations".

II. The megadungeon proper will be in and under the "Palace carved out of a mountain" in the above description and will be designed using the approach of the "Node-based-Megadungeon" found here http://www.kjd-imc.org/blog/node-based-megadungeon-design/ and improved upon here http://dungeonofsigns.blogspot.de/2013/02/megadungeon-thoughts-part-iii.html (the later article will also be my role-model for handling factions).
Therefore it will be mostly filled through random tables together with some set pieces.

Some of the ideas for Nodes so far are:
1. The Sunken Sun-Temple:  On top of the mountain in the middle of the city lie the ruins of a massive temple. It served as the entry for the expedition of 1892 into the air-filled dungeons and caverns beneath the city. Major entry point; lots of explorer-factions, maybe even a bridge head/base camp for expeditions into the dungeons (a version of the classic "village near the dungeon").

2. The Nether Necropolis: A vast complex of catacombs and elaborate tombs below the Sun-Temple. Inspired by the crypts of the Egyptians and the ancient civilizations of South America (which all developed out of Atlantean colonies according to the speculations of Ignatius Donelly in "Atlantis- the antediluvian world"), as well as by the hyperborean civilization in Mike Mignola's Hellboy comics. I imagine this part of the dungeon to be the most explored by the different surface-factions, so this will be a primary place for faction-play.

3. The Tunnels of the Tribes: Below the city of Atlantis there is a vast network of tunnels – remants of sewers, construction tunnels and maybe even ancient transportation systems. Many of these are partly air-filled, many are not. These tunnels are inhabited by savage tribes  of cannibalistic human-descended creatures who have adapted to a live in the dark waters (pale hairless skin, large eyes, pointed teeth, more subcutaneous fat in the right places to streamline the body, large webbed hand and feet – not fishlike like the typical lovecraftian Deep Ones, but more in the direction of seals (without the cute)). These tribes hunt for sea-life in the dark-tunnels, wage endless wars and raids against each other and worship strange idols in the dark.

4. Vaults of the Machines: Deep below the city of Atlantis ancient machines still serve long forgotten purposes. This node is inspired by the deep machine-level in the city of Zion in the matrix-trilogy, but far more alien and weird. Among other things these machines will serve as an excuse for breathable air within the dungeon. I imagine the technology more along the lines of the technology of the Great Race in Carcosa: For a victorian-era person it will be indistinguishable from magic. Crystals, strange lights, constructs from unknown materials, bio-robotics – all covered by strange sigils.

5. Forest of Bioluminescence: Vast caverns below the city are stretching into the unmeasured depths. A strange ecosystem has developed there, where glowing polyps, corals and seaweeds form a forest of light where strange creatures breed and hunt. It is also whispered among the tribes that a big evil slumbers away the eons there, something that shall only wake when the world is about to end. Deep Sea meets the Underdark. A high-pressured hex-crawl.

6. Graveyard of Ships: Thousands of shipwrecks from all the ages of men lie on the bottom of the sea in Atlantis. At one point next to the central mountain they form a giant castle-like structure. Strange lights are sometimes seen inside the castle of wrecks and it is rumored that an ancient sea-hag lives there with her daughters and her slaves, collecting the souls of drowned sailors to trade them to otherworldly evils for knowledge and power. Dungeon made out of shipwrecks, folkloric witch-magic, undead sailors from all ages, Davy Jones Locker (of course inspired by the Hellboy-comic "The Third Wish" in "Strange Places").

Your opinions? Other ideas?

By the way, I am a big fan of Mike Mignola's Hellboy universe and the comics will probably be one of the main inspirational material.

Has anyone mentioned the old George Pal movie 'Atlantis: the Lost Continent'? It's pretty gonzo... giant crystal energy rays, magically mutated boar-men, exploding volcanoes...
Or 'Captain Nemo and the Underwater City'.
There seems to have been some Captain Nemo series with Omar Sharif as Nemo... something new to track down.

Quote from: Demidian;858535Thank you for all the input - I have already started to read some of your suggestions and the atlantis disney movie is scheduled to be watched the coming weekend.

Some additional ideas I had concerning my setting:

I. Plato in the Critias gives a description of Atlantis (cited from Wikipedia):
 
"Poseidon carved the mountain where his love dwelt into a palace and enclosed it with three circular moats of increasing width, varying from one to three stadia and separated by rings of land proportional in size. The Atlanteans then built bridges northward from the mountain, making a route to the rest of the island. They dug a great canal to the sea, and alongside the bridges carved tunnels into the rings of rock so that ships could pass into the city around the mountain; they carved docks from the rock walls of the moats. Every passage to the city was guarded by gates and towers, and a wall surrounded each of the city's rings. The walls were constructed of red, white and black rock quarried from the moats, and were covered with brass, tin and the precious metal orichalcum, respectively."

So, like this:


I want to develop a mechanic for explorations with a submarine in the ruins of Atlantis connected with diving expeditions. I thought of maybe using the city-crawling rules in Vornheim (maybe together with an Antlantean alphabet like this one
instead of the standard one) to create the basic layout of the ruined city combined with a hacked version of the "Instant Location"-generators found in A Red and Pleasant Land to create content for more detailed "diving-expedition-adventure-locations".

II. The megadungeon proper will be in and under the "Palace carved out of a mountain" in the above description and will be designed using the approach of the "Node-based-Megadungeon" found here http://www.kjd-imc.org/blog/node-based-megadungeon-design/ and improved upon here http://dungeonofsigns.blogspot.de/2013/02/megadungeon-thoughts-part-iii.html (the later article will also be my role-model for handling factions).
Therefore it will be mostly filled through random tables together with some set pieces.

Some of the ideas for Nodes so far are:
1. The Sunken Sun-Temple:  On top of the mountain in the middle of the city lie the ruins of a massive temple. It served as the entry for the expedition of 1892 into the air-filled dungeons and caverns beneath the city. Major entry point; lots of explorer-factions, maybe even a bridge head/base camp for expeditions into the dungeons (a version of the classic "village near the dungeon").

2. The Nether Necropolis: A vast complex of catacombs and elaborate tombs below the Sun-Temple. Inspired by the crypts of the Egyptians and the ancient civilizations of South America (which all developed out of Atlantean colonies according to the speculations of Ignatius Donelly in "Atlantis- the antediluvian world"), as well as by the hyperborean civilization in Mike Mignola's Hellboy comics. I imagine this part of the dungeon to be the most explored by the different surface-factions, so this will be a primary place for faction-play.

3. The Tunnels of the Tribes: Below the city of Atlantis there is a vast network of tunnels – remants of sewers, construction tunnels and maybe even ancient transportation systems. Many of these are partly air-filled, many are not. These tunnels are inhabited by savage tribes  of cannibalistic human-descended creatures who have adapted to a live in the dark waters (pale hairless skin, large eyes, pointed teeth, more subcutaneous fat in the right places to streamline the body, large webbed hand and feet – not fishlike like the typical lovecraftian Deep Ones, but more in the direction of seals (without the cute)). These tribes hunt for sea-life in the dark-tunnels, wage endless wars and raids against each other and worship strange idols in the dark.

4. Vaults of the Machines: Deep below the city of Atlantis ancient machines still serve long forgotten purposes. This node is inspired by the deep machine-level in the city of Zion in the matrix-trilogy, but far more alien and weird. Among other things these machines will serve as an excuse for breathable air within the dungeon. I imagine the technology more along the lines of the technology of the Great Race in Carcosa: For a victorian-era person it will be indistinguishable from magic. Crystals, strange lights, constructs from unknown materials, bio-robotics – all covered by strange sigils.

5. Forest of Bioluminescence: Vast caverns below the city are stretching into the unmeasured depths. A strange ecosystem has developed there, where glowing polyps, corals and seaweeds form a forest of light where strange creatures breed and hunt. It is also whispered among the tribes that a big evil slumbers away the eons there, something that shall only wake when the world is about to end. Deep Sea meets the Underdark. A high-pressured hex-crawl.

6. Graveyard of Ships: Thousands of shipwrecks from all the ages of men lie on the bottom of the sea in Atlantis. At one point next to the central mountain they form a giant castle-like structure. Strange lights are sometimes seen inside the castle of wrecks and it is rumored that an ancient sea-hag lives there with her daughters and her slaves, collecting the souls of drowned sailors to trade them to otherworldly evils for knowledge and power. Dungeon made out of shipwrecks, folkloric witch-magic, undead sailors from all ages, Davy Jones Locker (of course inspired by the Hellboy-comic "The Third Wish" in "Strange Places").

Your opinions? Other ideas?

By the way, I am a big fan of Mike Mignola's Hellboy universe and the comics will probably be one of the main inspirational material.

this is great. the best thread in ages.