I'm running a 5e campaign on Thursday now, but it was arranged via Meetup, and I had literally no idea if I was going to get one player or nine. I also wasn't entirely sure what the players who showed up would want to do. But I figured I had to have something to show, so here's what I came up with.
Note that I was attempting to provide an efficient way to reach every possible kind of common adventure in a relatively simple 3-by-3ish array of home areas (from tropical island to Underdark), and to give the campaign a simple framework that would allow me to spin off stories from PC's personal backgrounds OR simply drop a dungeon in front of a random group of players. I think I succeeded, and I have to thank The Nightmares Underneath for providing the basic background that I'm stealing. Also, we had a great time, so I'm quite happy. *******
WELCOME TO NIGHTMARES OVER NEW HARBOR!
ABOUT NEW HARBOR
New Harbor is a relatively young, diverse, and fast-growing coastal town in the world of Panora with an unexplored wilderness to the west and a series of older, independent, and expansionist kingdoms to the east, any one of whom would love to conquer New Harbor if only it weren’t in such a dangerous location. The danger is not just the crime--although the closer you get to harborside, the more New Harbor becomes a den of crime and piracy--but it’s the unknowns all around it...especially, most recently, the Nightmare Dungeons.
ABOUT THE NIGHTMARE DUNGEONS
For some reason--probably because of the nearby Sundered Hills (q.v.)--New Harbor is very close to the wall between the worlds, making it of unusual interest to the gods, the feywild, extraplanar demons, the Outer Things (the three sources of warlock power), and the Land of Dreams. It’s because of this last connection that New Harbor has begun facing incursions from the realm of Nightmares. These incursions take the form of dungeons that appear--usually as a simple doorway in a wall or a mountainside--and start leaking monsters into our world.
Dungeons not only leak monsters into our world, but their very presence tends to create illness, madness, and even mutations in everyone who lives nearby when one appears. The way to kill a dungeon is to enter it, kill the “crown” (the boss monster), and remove the “anchor” (a specific treasure of usually high value) to our world. This severs the dungeon’s connection to our plane. But very few are able to do this difficult work.
Adventurers in this world are all “dream-touched,” which means that, for whatever reason--through blood or accident or nature--they can travel to other planes without losing sanity, and this means they can enter Nightmare Dungeons without taking damage every turn. (It also explains why PC spellcasters can handle magic at all!) Ever since the Nightmare Incursion began six months ago, people who are dream-touched are in high demand.
As the campaign opens, there are 21 NIghtmare Incursions that travelers have clearly identified. When all of them are killed, the campaign can end.
ABOUT PANORA
The world of Panora is bascially a standard 5e system, with all the usual races from the Players Handbook, as well as kenku (bird-people), tabaxi (cat-people), and tortles (turtle-people) from the Forgotten Realms. We use the standard array for characteristics, with one exception: Humans get a +1 to each of their six characteristics, while nonhuman races just use the standard array, with their usual racial modifiers. (Reason: nonhuman races in 5e have so many special powers, humans need a boost in characteristics to even things out.)
WHAT EVERY PC IN NEW HARBOR KNOWS
New Harbor is a bustling city with a significant, but not overwhelming, criminal element. (Think Haven from Thieves’ World: seedy but functional.) You can find every type of person and every sort of business within its walls, from mad wizards to tabaxi merchants to imperial troops who are very far from home. If you need it, you can buy it. If you have it to sell, someone will want it.
Just south of New Harbor is its most important feature: The Sundered Hills. Originally a spike of rock that used to be four mountains, some massive divine or arcane power shattered them to the core a few decades back so that now they are blackened, hill-sized...and they contain a giant crack (The Great Chasm or The Shadow Door) that leads deep underground. Part of this path leads to the Underdark and its evil inhabitants, while another branch leads to the baffling cities of the Precursors, a long-dead saurian people whose crystal-based technology is indistinguishable from magic and unfathomable to us today. The Precursors did a lot of work on and around other planes--this may be why they vanished--and this is why most people assume New Harbor is facing incursions from Nightmare now.
To the immediate north is the Aqua Thooly, The Far Water, an ocean whose full distance has never been explored--though there are rumors of a cluster of land masses called the Isles of Mystery, less than a month to the northeast.
To the east is The Black Marsh, which is where several early (but post-Precursor) civilizations have been born and then collapsed. The place is full of undead, weird, and aberrant creatures that live in and among the ruined temples, tombs, and other buildings, many of which have been untouched for hundreds of years. Buildings are forever rising and sinking here.
To the west is The Cold Desert, which--it is rumored from the few who have crossed it--leads ultimately to the city of Glinn, a metropolis of golden spires, floating ships, and strange mechanical devices which is ruled by wizards of unknown power. If you run across something truly bizarre, it probably hails from Glinn. (Think Eberron by way of India/Arabia, only cold.)
Beyond the Sundered Hills there are The Walled Mountains (an incredibly high rocky range that most go around), The Grand Plain (just south of the desert; a favorite site for wizards who want to build towers) and The Wild Forest (south of the marshes). Somewhere to the south of these are the two major cities who occasionally threaten New Harbor: rigidly ruthless Elnora (sort of a lawful neutral city-state; Queen Adina), and sneaky and conniving Canis (chaotic neutral; King Radivar).
And even farther to the south is Primus, the home of the putative Panoran Empire, a once-thriving state (they funded the founding of New Harbor) that is currently under the rule of a foolish teenager (His Imperial Majesty Garabald XXIII) who is letting his hold slip, which is allowing Elnora and Canis to imagine themselves independent. The Empire mostly ignores New Harbor unless something financially important is at stake.
(Note: I realize these names are kind of stupid and on the nose. My desire is to make them really really easy to remember, so none of my players have to do homework.)