I wasn't sure where to put this, so I figured Gaming Discussions for a discussion on D&D. If it should go elsewhere, someone please let me know.
WARNING: This is a very long and detailed article basically outlining my latest and greatest campaign setting. I am coming up with this as I go along, so don't be surprised if I switch gears and topics oddly along the way. Oh, and I make mention of a previous game idea I had involving goblins/cosmic horrors, ignore that bit, it probably won't make sense without the proper context anyways.
So now I appear to be at a crossroads on which campaign to play. I came up with another idea that I believe is more fun and original than my goblin idea. The idea is more involved and requires a few assumptions about the campaign setting and the origins of monsters that are going to require some detail. Here we go:
An obscure demiplane, who's name is long forgotten, houses a dungeon of staggering size. In truth this dungeon is endless and infinite in size as the plane has no boundaries. This demiplane is sentient, a genius loci, created for some fell purpose before mortal races walked the world. Perhaps it was an early creation of the Primordials, something from before the World was forged. Maybe the plane is a Primordial, chained for so long that it fused with its prison. Regardless of the nature of the plane, it intentions are clear. When a place falls to ruin and enough time has passed to give rise to legends and myths, the barriers between the planes becomes thin in that area and Dungeon begins to bleed into the World. Chaos usually follows.
Essentially, the barriers becomes weak because the place becomes less real the more legends and stories are created around it. The less truth is known about a place, the less "real" it becomes in a mystical sense. Conversely, if there are little to no stories about a place, the less likely it is that Dungeon will seep through, unless other circumstances thin the barriers.
Stories about a place can include just about anything as long the story twists the truth and gives other falsities. For example, a Dungeon might spawn in the basement of a ruined tower because local legends say that the tower once housed a powerful wizard who died under very mysterious circumstances, and as such, his ghost now haunts the premises. Now all of this makes for a nice tale, but the reality is that the tower was built as a scouting post for soldiers centuries ago. The kingdom that ruled the area fell long ago and has since been forgotten by the locals (although research could reveal the true history if you want), as a result the local legend is just that, a legend. The basement of a "haunted" manor would be a good place for urban campaigns, or the alleged "torture rooms" in the depths of a castle.As long as the story is widely believed and the place is thought of by the local as a ruin (this last proviso allows dungeons in places that might be dilapidated or condemned, but still populated. The aforementioned "haunted" manor is even more fun if it's occupied by a crazy shut in, for example), the possibilities are endless.
Now, it should be noted that the Dungeon is not all connected. You won't enter a Dungeon in one place and exit elsewhere halfway around the world unless the Dungeon physically runs that far. Similarly, it is not a reliable method of extra planar travel even if it can be accessed for other planes. It's connected everywhere, basically like Sigil, but a dungeon instead of a city. Two nearby Dungeons instinctively grow towards each other, looking to join and become one large complex. They then seek out other nearby Dungeons and so on. This means that a Dungeon could be the only means of travel between two disparate regions if that dungeon, say, cuts through a mountain. It's one of the strange conundrums of the Dungeon, when you cross the threshold into the Dungeon, you physically leave this plane. You are IN Dungeon. Yet, other sections of the Dungeon cannot be accessed by, say, digging through an "outside" wall. You would dig forever and never breach another wall. Yet, two people who entered Dungeon from two separate entrances are considered to be on the same plane, only infinitely apart. In the aforementioned "cut through a mountain" situation, the Dungeon is exactly the same size it would be if it were in the World, even if it isn't actually located there.
So, we covered where the Dungeon comes from and some basics on their large scale design, now for the fun part, population and architecture (a.k.a.: encounters and loot)
The Dungeon is single minded in its purpose. It is the embodiment of the very concept of the D&D dungeon. It seeks to create a endless network of trials and traps to test the races of the cosmos. The oldest and largest Dungeons house powerful artifacts, lost secrets and wealth beyond imagining. Powerful demons, liches, even gods purposefully place their valuables deep within its endless depths. With the aid of inter-planar teleportation circles, vaults can essentially be created by those with the power.
When a Dungeon is new, it starts off as little more than a short corridor that ends abruptly. As times goes on, the hallway deepens and branches, forming rooms. Traps begin to appear, simple at first, but so do the first low-level treasures. They come into existence seemingly from nothing, the raw elemental stuff that is needed is pulled directly from the Elemental Chaos and given form (which further strengthens the Primordial angle). The rooms change configuration and size to accommodate it's inhabitants, the surrounding geography of the corresponding World and the whims of its chaotic intelligence.
Depending on how you want to interpret it, the Dungeon either attracts nearby monsters to live in it, inexplicably spawns them from nothing or some combination of the two (my favorite). Going with the last, we can assume that most of the humanoid races existed before the Dungeon started seeping into the World. After all, you need sentient creatures to give places the stories that disconnect them from reality. And of course, there are going to be strange and powerful creatures that exist regardless of the Dungeon. Pick whatever you want, I like the thought of humanoids, dragons and a few other staples existing regardless of the Dungeons presence.
Savage humanoid tribes tend to migrate to Dungeons when they hear that one has appeared the region. Survivors of the initial forays will find that the longer they live in the Dungeon, the more it seems the recognize them as belonging. Rooms slowly shift to meet the needs new members. If you bring in furniture, you will find that as new rooms are created, they are furnished in the most common style. Wells with drinkable, if tasteless, water will be made in rooms near creatures that require it. Traps begin to appear in locations advantageous to the inhabitants (although often without them knowing about it), often protecting them from would be treasure seekers. Goblins and kobolds in particular, with their...vigorous breeding habits, are always on the lookout for young Dungeons that expand to meet their needs without their having to dig for themselves. Life in the Dungeon is never easy however, as it recognizes many strange and dangerous species, many of which instinctively know how to avoid traps by dint of having been spawned by the Dungeon itself.
Truly bizarre creatures like oozes, aberrations, the weirder magical beasts and so on, come into existence from within Dungeon. Much like traps, treasure and other objects, these creatures come into existence fully formed from raw elemental energy. They prowl the depths of the dungeon feeding on other, weaker creatures in an endless cycle death and creation (again, Primordials). The age of the dungeon determines the level of the creatures spawned within it. The specifics are irrelevant, this just gives you an excuse to have otherwise disparate creatures of roughly the same level in the same dungeon. The Dungeon spawned it. As the Dungeon grows older and the number of rooms and hallways increase, so does the level of the traps, creatures and treasure spawned within it. Humanoid inhabitants are constantly exploring new depths in search of valuables, but the deeper they go, the worse the danger. Eventually, everything in the Dungeon will be killed or subjugated by stronger and stronger beings. Every so often, a creature or even group of creatures created within the Dungeon leaves its confines. This has led to the proliferation of many of the beasts now terrorizing the World. Carrion crawlers set up a nest and are infesting your sewers? Probably escaped from a nearby dungeon. Reasons for leaving are as varied as there are creatures, but many that leave are forced out by the presence of increasingly stronger predators. The nature of the Dungeon demands the strongest, and eventually a creature living in a Dungeon will either have to choose to stay and starve since he can't find weaker prey or leave and try their luck on the outside. An interesting (and amusing) side effect of being able to spawn creatures at will is the ability to run truly random encounters without feeling bad. Party decides to camp in the dungeon for the night? Check for Random Encounter! Oh, they cleared it out did they? We'll see about that *rolls d20*.
Exceptionally large Dungeons do exist, but can be a hassle to run. The largest are mostly empty but are punctuated by more heavily populated areas. Long stretches of hallways give way to bridges overarching vast underground canyons give way large halls give way to etc... I'm thinking of running encounter "segments" for these areas. Basically, the party wanders Moria for a while, but when you want an encounter you just draw your dungeon section with exits at the edge of the map that go further into the dungeon. There's no point in drawing out dozens, possibly hundreds of empty rooms and hallways. Just make the sections that have stuff worth interacting with. This is especially useful if you use a Dungeon as a highway of sorts. Make some wildly imaginative dungeon environments, no real explanation is given or needed, that's just the way the Dungeon is. Have a little adventure, slay some monsters, get some loot, continue on through the Dungeon.
Finding and entering a Dungeon for the first time is often disorienting. The gateway between the two worlds is subtle and not immediately noticed. You'll be walking down the down a mineshaft the locals claim is cursed when you suddenly notice that you've been walking on smooth cobblestone for the past 5 seconds. The hallways are 10' wide by 10' tall, torches are evenly spaced along the walls. You turn around and see the passage plunge into darkness behind you. Surely you haven't walked that far? As a matter of fact, if you were to turn around and head the other way, you would eventually find yourself walking through the mineshaft once more, unsure of where the cobblestone ended and the rough rock begins. The entrance will always occur in the same area however and generally appear as part of hallways or thresholds. If you dig around the area you believe the gate to be located you will find that you will still enter the Dungeon, but only if you are within 20' of the tunnel where the gate is located. Otherwise, you can successfully dig around the gate and access whatever the gate is blocking if you come at it from another direction.
So now we have a dungeon populated and filled with traps and loot. We have covered basic ecology (it works because the dungeon says so), how dungeons appear, spread and how their denizens can effect the World. But the question is Why? and How Do We Stop It?
Tackling the later question first, it was earlier explain that Dungeon follows a certain alien logic. That of the consummate dungeon. Yes, it has traps, monsters, curses, demons, rivers of lava etc... but it rewards you for it, thank you very much. As soon as Dungeon touches this World, a keystone is created, linking it to the World. This keystone changes from Dungeon to Dungeon, but it's purpose is always the same, keep the connection between the Dungeon and the World active, allowing Dungeon to grow. Sometimes the keystone is an object created within the Dungeon, sometimes a creature, but always exceptional in some way. A beautiful mirror, the unusually intelligent leader of a pack of Displacer Beasts, a holy symbol found in the dungeon and now worn by a cleric of Vecna now living in the Dungeon. Whatever you want. Destruction of the keystone or removal of the keystone from the Dungeon causes the gateway to collapse and close. The party is ejected out the nearest entrance. They suddenly just appear there with all their carried possessions on hand. This could be amusing when the multi-floored hell they just went through turns out to be a wine cellar. Anything not carried on their person in lost to Dungeon and nothing short of a powerful inter-planar travel spell will get you or your items back. Once sealed, the gate will not reappear in the same exact location twice. An interesting side effect to sealing a Dungeon is the popularity of the local legends about the place it's located seems to diminish. This in turn reinforces the barrier between the world and helps prevent further intrusion. Some locations are so legendary however, that it's only a matter of time before another dungeon appears, this time the gate simply appearing in a different hall or doorway. If left unchecked, they will regrow to their previous size and strength.
So the Big Question. Why? I believe I am going to go choose the middle-ground again and decide that Dungeon was originally a Primordial. He was bound to an unfinished demiplane during the Dawn War. This demiplane was an earlier creation of the Primordials, predating the World. A fragment remained and was found by the Gods and they used it to seal away one of the strongest Primordials. So effective was his imprisonment that history never recorded his existence. Little did the Gods know however, the demiplane was created with a fragment of crystal cut from the same stone as the Heart of The Abyss. It lacked the evil of the Heart however, this was a shard of pure Chaos. A pure fragment of the original founding stone of the Creation. After a length of time that would see the world broken and remade again over geological epochs, the Primordial lost its mind while its body and consciousness merged with the demiplane, becoming one with the very fabric of existence within the demiplane. This gave it total control of virtually every aspect of the plane. But much like a person's heart beats without him thinking about it, so do aspects of the plane fall outside of Dungeons control. Even though its mind has fused with demiplane, Dungeon is unable to access the full power of the crystal, which is located at the exact center of the infinitely large plane (try not to think about it too hard). Although it is known that Dungeons grown towards each other, what none but Dungeon know (for now, of course) is that when they aren't reaching out for each other (i.e.: moving more or less horizontal under the ground) they grow down like roots. It is thought that should Dungeon reach the center of the its prison, it will gain the full power of the crystal and possibly be able to break out, materializing as an infectious genius loci in the world. If this were to occur, it would continue to grow, but this time it would be physically Here, and this plane isn't infinite large. Odds are Dungeon would assimilate the entire plane before starting on other planes of existence. Basically a Reality-Ending event.
So the party will most likely start out with a very similar startup to my goblin campaign idea, expect in this case, the goblin are attracted to the valley due to the appearance of a dungeon in the nearby "haunted" woods. First the goblins need to be stopped, they are using the Dungeons to expand their territory and their encampments have been popping up everywhere. Eventually, the Dungeon will have to be delved and sealed, making the area a little safer and hopefully driving off the goblins. As the game progress, more and more unusual creature will be encountered as the number of Dungeons appearing in the world increases. The party will need to step up to stop the rise in monsters as well as those who are taking advantage of the decaying state of the world. As Dungeon approaches its goal (and it will, remember it can connect to any plane anywhere, so you can't close all the portals), the Heart of Chaos (as we shall now call the crystal) begins to corrupt the World. Natural disaster become commonplace as the metaphysical laws placed by the Gods to keep the world fixed begin to unravel and the World become more and more mutable. At it's finale (whenever that is), the party will have to acquire a teleportation circle address to the center of Dungeon where they will face off with the physical avatar of Dungeon (which will probably be styled after the Zeitgeist from Cityscape (3.5e). If they succeed, they save reality, seal away the Heart of Chaos forever and become heroes of truly epic scope (pun intended). If they fail, the World will be unmade and reformed in the image of its new, twisted master. The running metaphor if you really need one, is that the world is an apple and Dungeon is the worm eating away at from the inside. The Chaos first starts with minds of the weak, affecting animals and the weak-willed, this will make up the bulk of Heroic play. Add in the odd Dungeon and people going mad from it's proximity and there are levels worth of fun to be had. Paragon tier will focus on a major villain introduced near the end of Heroic tier. This will be plot B and will focus less of the invasion of Dungeon and more on a second plot I plan to write (maybe the goblin/cosmic horror plot? Run both, just end plot B in early Epic tier (21-24) and use the last bit to wrap up plot A and save reality.
So that's it. That's my campaign setting outline. I hope you enjoyed it and if you have interesting suggestions feel free to mention them. Much more work will go into this, cleaning it up, organizing the information better, fleshing out the world proper. This is all for a game I'm running next week, so there's lots of work to be done!
WARNING: This is a very long and detailed article basically outlining my latest and greatest campaign setting. I am coming up with this as I go along, so don't be surprised if I switch gears and topics oddly along the way. Oh, and I make mention of a previous game idea I had involving goblins/cosmic horrors, ignore that bit, it probably won't make sense without the proper context anyways.
So now I appear to be at a crossroads on which campaign to play. I came up with another idea that I believe is more fun and original than my goblin idea. The idea is more involved and requires a few assumptions about the campaign setting and the origins of monsters that are going to require some detail. Here we go:
An obscure demiplane, who's name is long forgotten, houses a dungeon of staggering size. In truth this dungeon is endless and infinite in size as the plane has no boundaries. This demiplane is sentient, a genius loci, created for some fell purpose before mortal races walked the world. Perhaps it was an early creation of the Primordials, something from before the World was forged. Maybe the plane is a Primordial, chained for so long that it fused with its prison. Regardless of the nature of the plane, it intentions are clear. When a place falls to ruin and enough time has passed to give rise to legends and myths, the barriers between the planes becomes thin in that area and Dungeon begins to bleed into the World. Chaos usually follows.
Essentially, the barriers becomes weak because the place becomes less real the more legends and stories are created around it. The less truth is known about a place, the less "real" it becomes in a mystical sense. Conversely, if there are little to no stories about a place, the less likely it is that Dungeon will seep through, unless other circumstances thin the barriers.
Stories about a place can include just about anything as long the story twists the truth and gives other falsities. For example, a Dungeon might spawn in the basement of a ruined tower because local legends say that the tower once housed a powerful wizard who died under very mysterious circumstances, and as such, his ghost now haunts the premises. Now all of this makes for a nice tale, but the reality is that the tower was built as a scouting post for soldiers centuries ago. The kingdom that ruled the area fell long ago and has since been forgotten by the locals (although research could reveal the true history if you want), as a result the local legend is just that, a legend. The basement of a "haunted" manor would be a good place for urban campaigns, or the alleged "torture rooms" in the depths of a castle.As long as the story is widely believed and the place is thought of by the local as a ruin (this last proviso allows dungeons in places that might be dilapidated or condemned, but still populated. The aforementioned "haunted" manor is even more fun if it's occupied by a crazy shut in, for example), the possibilities are endless.
Now, it should be noted that the Dungeon is not all connected. You won't enter a Dungeon in one place and exit elsewhere halfway around the world unless the Dungeon physically runs that far. Similarly, it is not a reliable method of extra planar travel even if it can be accessed for other planes. It's connected everywhere, basically like Sigil, but a dungeon instead of a city. Two nearby Dungeons instinctively grow towards each other, looking to join and become one large complex. They then seek out other nearby Dungeons and so on. This means that a Dungeon could be the only means of travel between two disparate regions if that dungeon, say, cuts through a mountain. It's one of the strange conundrums of the Dungeon, when you cross the threshold into the Dungeon, you physically leave this plane. You are IN Dungeon. Yet, other sections of the Dungeon cannot be accessed by, say, digging through an "outside" wall. You would dig forever and never breach another wall. Yet, two people who entered Dungeon from two separate entrances are considered to be on the same plane, only infinitely apart. In the aforementioned "cut through a mountain" situation, the Dungeon is exactly the same size it would be if it were in the World, even if it isn't actually located there.
So, we covered where the Dungeon comes from and some basics on their large scale design, now for the fun part, population and architecture (a.k.a.: encounters and loot)
The Dungeon is single minded in its purpose. It is the embodiment of the very concept of the D&D dungeon. It seeks to create a endless network of trials and traps to test the races of the cosmos. The oldest and largest Dungeons house powerful artifacts, lost secrets and wealth beyond imagining. Powerful demons, liches, even gods purposefully place their valuables deep within its endless depths. With the aid of inter-planar teleportation circles, vaults can essentially be created by those with the power.
When a Dungeon is new, it starts off as little more than a short corridor that ends abruptly. As times goes on, the hallway deepens and branches, forming rooms. Traps begin to appear, simple at first, but so do the first low-level treasures. They come into existence seemingly from nothing, the raw elemental stuff that is needed is pulled directly from the Elemental Chaos and given form (which further strengthens the Primordial angle). The rooms change configuration and size to accommodate it's inhabitants, the surrounding geography of the corresponding World and the whims of its chaotic intelligence.
Depending on how you want to interpret it, the Dungeon either attracts nearby monsters to live in it, inexplicably spawns them from nothing or some combination of the two (my favorite). Going with the last, we can assume that most of the humanoid races existed before the Dungeon started seeping into the World. After all, you need sentient creatures to give places the stories that disconnect them from reality. And of course, there are going to be strange and powerful creatures that exist regardless of the Dungeon. Pick whatever you want, I like the thought of humanoids, dragons and a few other staples existing regardless of the Dungeons presence.
Savage humanoid tribes tend to migrate to Dungeons when they hear that one has appeared the region. Survivors of the initial forays will find that the longer they live in the Dungeon, the more it seems the recognize them as belonging. Rooms slowly shift to meet the needs new members. If you bring in furniture, you will find that as new rooms are created, they are furnished in the most common style. Wells with drinkable, if tasteless, water will be made in rooms near creatures that require it. Traps begin to appear in locations advantageous to the inhabitants (although often without them knowing about it), often protecting them from would be treasure seekers. Goblins and kobolds in particular, with their...vigorous breeding habits, are always on the lookout for young Dungeons that expand to meet their needs without their having to dig for themselves. Life in the Dungeon is never easy however, as it recognizes many strange and dangerous species, many of which instinctively know how to avoid traps by dint of having been spawned by the Dungeon itself.
Truly bizarre creatures like oozes, aberrations, the weirder magical beasts and so on, come into existence from within Dungeon. Much like traps, treasure and other objects, these creatures come into existence fully formed from raw elemental energy. They prowl the depths of the dungeon feeding on other, weaker creatures in an endless cycle death and creation (again, Primordials). The age of the dungeon determines the level of the creatures spawned within it. The specifics are irrelevant, this just gives you an excuse to have otherwise disparate creatures of roughly the same level in the same dungeon. The Dungeon spawned it. As the Dungeon grows older and the number of rooms and hallways increase, so does the level of the traps, creatures and treasure spawned within it. Humanoid inhabitants are constantly exploring new depths in search of valuables, but the deeper they go, the worse the danger. Eventually, everything in the Dungeon will be killed or subjugated by stronger and stronger beings. Every so often, a creature or even group of creatures created within the Dungeon leaves its confines. This has led to the proliferation of many of the beasts now terrorizing the World. Carrion crawlers set up a nest and are infesting your sewers? Probably escaped from a nearby dungeon. Reasons for leaving are as varied as there are creatures, but many that leave are forced out by the presence of increasingly stronger predators. The nature of the Dungeon demands the strongest, and eventually a creature living in a Dungeon will either have to choose to stay and starve since he can't find weaker prey or leave and try their luck on the outside. An interesting (and amusing) side effect of being able to spawn creatures at will is the ability to run truly random encounters without feeling bad. Party decides to camp in the dungeon for the night? Check for Random Encounter! Oh, they cleared it out did they? We'll see about that *rolls d20*.
Exceptionally large Dungeons do exist, but can be a hassle to run. The largest are mostly empty but are punctuated by more heavily populated areas. Long stretches of hallways give way to bridges overarching vast underground canyons give way large halls give way to etc... I'm thinking of running encounter "segments" for these areas. Basically, the party wanders Moria for a while, but when you want an encounter you just draw your dungeon section with exits at the edge of the map that go further into the dungeon. There's no point in drawing out dozens, possibly hundreds of empty rooms and hallways. Just make the sections that have stuff worth interacting with. This is especially useful if you use a Dungeon as a highway of sorts. Make some wildly imaginative dungeon environments, no real explanation is given or needed, that's just the way the Dungeon is. Have a little adventure, slay some monsters, get some loot, continue on through the Dungeon.
Finding and entering a Dungeon for the first time is often disorienting. The gateway between the two worlds is subtle and not immediately noticed. You'll be walking down the down a mineshaft the locals claim is cursed when you suddenly notice that you've been walking on smooth cobblestone for the past 5 seconds. The hallways are 10' wide by 10' tall, torches are evenly spaced along the walls. You turn around and see the passage plunge into darkness behind you. Surely you haven't walked that far? As a matter of fact, if you were to turn around and head the other way, you would eventually find yourself walking through the mineshaft once more, unsure of where the cobblestone ended and the rough rock begins. The entrance will always occur in the same area however and generally appear as part of hallways or thresholds. If you dig around the area you believe the gate to be located you will find that you will still enter the Dungeon, but only if you are within 20' of the tunnel where the gate is located. Otherwise, you can successfully dig around the gate and access whatever the gate is blocking if you come at it from another direction.
So now we have a dungeon populated and filled with traps and loot. We have covered basic ecology (it works because the dungeon says so), how dungeons appear, spread and how their denizens can effect the World. But the question is Why? and How Do We Stop It?
Tackling the later question first, it was earlier explain that Dungeon follows a certain alien logic. That of the consummate dungeon. Yes, it has traps, monsters, curses, demons, rivers of lava etc... but it rewards you for it, thank you very much. As soon as Dungeon touches this World, a keystone is created, linking it to the World. This keystone changes from Dungeon to Dungeon, but it's purpose is always the same, keep the connection between the Dungeon and the World active, allowing Dungeon to grow. Sometimes the keystone is an object created within the Dungeon, sometimes a creature, but always exceptional in some way. A beautiful mirror, the unusually intelligent leader of a pack of Displacer Beasts, a holy symbol found in the dungeon and now worn by a cleric of Vecna now living in the Dungeon. Whatever you want. Destruction of the keystone or removal of the keystone from the Dungeon causes the gateway to collapse and close. The party is ejected out the nearest entrance. They suddenly just appear there with all their carried possessions on hand. This could be amusing when the multi-floored hell they just went through turns out to be a wine cellar. Anything not carried on their person in lost to Dungeon and nothing short of a powerful inter-planar travel spell will get you or your items back. Once sealed, the gate will not reappear in the same exact location twice. An interesting side effect to sealing a Dungeon is the popularity of the local legends about the place it's located seems to diminish. This in turn reinforces the barrier between the world and helps prevent further intrusion. Some locations are so legendary however, that it's only a matter of time before another dungeon appears, this time the gate simply appearing in a different hall or doorway. If left unchecked, they will regrow to their previous size and strength.
So the Big Question. Why? I believe I am going to go choose the middle-ground again and decide that Dungeon was originally a Primordial. He was bound to an unfinished demiplane during the Dawn War. This demiplane was an earlier creation of the Primordials, predating the World. A fragment remained and was found by the Gods and they used it to seal away one of the strongest Primordials. So effective was his imprisonment that history never recorded his existence. Little did the Gods know however, the demiplane was created with a fragment of crystal cut from the same stone as the Heart of The Abyss. It lacked the evil of the Heart however, this was a shard of pure Chaos. A pure fragment of the original founding stone of the Creation. After a length of time that would see the world broken and remade again over geological epochs, the Primordial lost its mind while its body and consciousness merged with the demiplane, becoming one with the very fabric of existence within the demiplane. This gave it total control of virtually every aspect of the plane. But much like a person's heart beats without him thinking about it, so do aspects of the plane fall outside of Dungeons control. Even though its mind has fused with demiplane, Dungeon is unable to access the full power of the crystal, which is located at the exact center of the infinitely large plane (try not to think about it too hard). Although it is known that Dungeons grown towards each other, what none but Dungeon know (for now, of course) is that when they aren't reaching out for each other (i.e.: moving more or less horizontal under the ground) they grow down like roots. It is thought that should Dungeon reach the center of the its prison, it will gain the full power of the crystal and possibly be able to break out, materializing as an infectious genius loci in the world. If this were to occur, it would continue to grow, but this time it would be physically Here, and this plane isn't infinite large. Odds are Dungeon would assimilate the entire plane before starting on other planes of existence. Basically a Reality-Ending event.
So the party will most likely start out with a very similar startup to my goblin campaign idea, expect in this case, the goblin are attracted to the valley due to the appearance of a dungeon in the nearby "haunted" woods. First the goblins need to be stopped, they are using the Dungeons to expand their territory and their encampments have been popping up everywhere. Eventually, the Dungeon will have to be delved and sealed, making the area a little safer and hopefully driving off the goblins. As the game progress, more and more unusual creature will be encountered as the number of Dungeons appearing in the world increases. The party will need to step up to stop the rise in monsters as well as those who are taking advantage of the decaying state of the world. As Dungeon approaches its goal (and it will, remember it can connect to any plane anywhere, so you can't close all the portals), the Heart of Chaos (as we shall now call the crystal) begins to corrupt the World. Natural disaster become commonplace as the metaphysical laws placed by the Gods to keep the world fixed begin to unravel and the World become more and more mutable. At it's finale (whenever that is), the party will have to acquire a teleportation circle address to the center of Dungeon where they will face off with the physical avatar of Dungeon (which will probably be styled after the Zeitgeist from Cityscape (3.5e). If they succeed, they save reality, seal away the Heart of Chaos forever and become heroes of truly epic scope (pun intended). If they fail, the World will be unmade and reformed in the image of its new, twisted master. The running metaphor if you really need one, is that the world is an apple and Dungeon is the worm eating away at from the inside. The Chaos first starts with minds of the weak, affecting animals and the weak-willed, this will make up the bulk of Heroic play. Add in the odd Dungeon and people going mad from it's proximity and there are levels worth of fun to be had. Paragon tier will focus on a major villain introduced near the end of Heroic tier. This will be plot B and will focus less of the invasion of Dungeon and more on a second plot I plan to write (maybe the goblin/cosmic horror plot? Run both, just end plot B in early Epic tier (21-24) and use the last bit to wrap up plot A and save reality.
So that's it. That's my campaign setting outline. I hope you enjoyed it and if you have interesting suggestions feel free to mention them. Much more work will go into this, cleaning it up, organizing the information better, fleshing out the world proper. This is all for a game I'm running next week, so there's lots of work to be done!