In an effort of full disclosure I want to list some of my sources of inspiration for environmental aspects this particular vision of Icosa. I've posted before about the inspiration of opposition & situation elements, so no need to reiterate here.
Well WorldWhile I've never read this series of books by Jack L. Chalker, the premise has always stuck with me. I remember hearing about these books when a role-playing game based on the first book was released in 1985. The world, an experiment of a long lost race of advanced beings, is divided up into 1500+ hexes. Each hex is a self-contained world with unique life forms that would be used to seed life on new planets throughout the universe. This idea of a 'world full of worlds' has been lurking in the recesses of my mind ever since.
Campaign ideaA fellow gamer and friend from high school, Don, once proposed a campaign setting in which the mountain walls were impassible and that life was limited to the valleys formed within these granite 'bowls'. Here, the dwarves held sway over any passage between valleys, but have long since closed their doors, cutting off each valley from it's neighbors. This, probably more than anything else, was the seed that is developing into Icosa.
MoriaThe parallels between the dwarven retreat in Icosa and those in Tolkien's Moria are intentional. Moria, as James Maliszewski points out, is probably the best example of a megadungeon in fantasy literature.
DragonlanceThe reclusive dwarves of the Dragonlance setting are yet a further refinement of the archetypal image created by their Moria cousins.
Rose of the ProphetThese books by Hickman & Weis detail a fantasy setting where there are 20 deities who are actually facets of one greater deity. The organization of these deities around a vertex of a icosahedron are more support for the faceted aspects of Icosa. While I don't plan to have exactly 20 deities (I'm actually not sure how many deities there will be), I would like to play with the idea that the aspects of the lines and vertexes Icosa's mountain ranges can add thematic spice to each of the 20 regions. In this way, neighboring regions may have particular themes in common.
And last, but certainly not least...
d20The humble and instantly recognizable d20 is a symbol long associated with fantasy role-playing games. 'Nuff Said.
And there you have it. This, along with my earlier posts, should give a clearer picture of where Icosa, as I see it, originated.
Follow Your Bliss,