When I cobbled together the game world for my Sword Coast Ramblers adventure, I had a simple idea. Just throw all the official content from published 5e adventures on the map, and let the players choose where to go. The story evolves based on their interest, and I emphasize or back-burner plot points to suit the party. As of now, they've completed most of the adventure locations outlined in Lost Mine of Phandelver and Dragon of Icespire Peak, with a couple side treks including the haunted house from Ghosts of Saltmarsh, and the mansion from Candlekeep Mysteries. There's plenty of hints and glimpses and cameos of characters from other books, thanks to a scrying orb in the party's possession. Ravens call out incessantly as they navigate the Neverwinter Woods, and Morgantha the night hag from Curse of Strahd has a vendetta against our Cleric of Selune.
Of course, with a completionist party there runs a risk of outleveling the region. They don't want to leave any stone unturned, but the content itself could quickly become trivial. They're eager to break out into the greater north, and I have breadcrumbs at the ready from Rise of Tiamat and Storm King's Thunder. First though, all our current plot threads converge on the Sunless Citadel.
Lore wise, the Citadel is a fortress and shrine to the dragon Ashardalon that sunk underground during a cataclysm decades ago, including earthquakes and volcanic eruptions from mount Hotenaw. The dungeon involves warring factions of Kobolds and Goblins, a baby white dragon, the trail of a missing adventuring party, and hordes of blights spawning from a Gulthias Tree. There's items described in the adventure that offer hooks toward other locations, as well as a couple conveniently placed entrances to the Underdark. If this were World of Warcraft, we'd be looking at a zone's main dungeon that culminates the story so far.
Tying Things Together
I had several plot hooks in play that led here.
1. Cryovain, the titular Dragon of Icespire peak, had been placated with treasure earlier. On another meeting, the party countered her demand with the offer of a favor instead. So, she claimed something had been taken from her by the Drow (led by The Spider, a villain found in Wave Echo Cave), and brought underground where she can't reach it. She told the party they'd know it when they see it.
2. The blights, a Gulthias tree clipping, and Anchorites of Talos were all encountered throughout the region in the Woodland Manse and Thundertree ruins. The Emerald Enclave has been driven away, and the trail of the resident druid in Thundertree has gone cold with rumors that they'd gone mad.
3. Our Drow player character had a deep want to find a way to the Underdark and save a backstory character. I tied The Spider into the underground slave trade outlined in Out of the Abyss, and hinted that he traded something to the residents of the Citadel in exchange for passage. That player's left the table for the time being, but those same Underdark tunnels can be utilized as a way to nearby Gauntlgrym.
4. Our Kobold character was tasked at the outset to aid in the effort to drive off goblins and claim the citadel for his tribe, meaning the party won't want to fight everything they meet in there. Venomfang, the green dragon in the Thundertree Ruins, took great delight in watching the players and the cultists fight each other, and welcomed the same Kobold in his tower to parlay. After learning about Cryovain, he demanded that whatever it is she wants, the party brings it to him first.
You can imagine the reaction at the table when the party finally gets to Meepo's chamber in the dungeon, see the empty cage, and learn that he'd been raising Calcryx, a baby white dragon. Their original goal of eventually slaughtering Cryovain is suddenly very complicated. At this level they could easily take any of the dragons in play, but the idea of reuniting Cryovain and Calcryx holds the promise of having them leave peacefully, and opens them up as interesting characters. Venomfang as a threat, or an opportunity to betray Cryovain gives some player choice and the ability to consider a much darker route for how to play things out.
Making Things Interesting
The only problem with the Sunless Citadel? This dungeon is designed for Level 1 characters, and after adventuring for months and checking things off the list, we're levels 5 and 6. The party could one-shot most of the threats in the dungeon, and that's just not interesting or fun. I found guidance to swap in some higher level stat blocks for the creatures that exist there, but I also needed to keep running with this theme of monsters as characters. The Foreward to Curse of Strahd talks about how disinteresting a game gets when the residents of a dungeon have no reason to be there aside from combat, and I take that to heart. What's going on here, and how is the party going to interact?
The upper level is easy: Kobolds vs Goblins. There's no doubt the party would side with the Kobolds. but knowing their goal is to take Calcryx out with them puts them at odds. They needed to find a way to get the dragon out of the dungeon without angering or killing its keepers. Promising Meepo that he can keep caring for the dragon on the surface, and plotting a stealthy escape route made for an exciting mini-heist. They spun a yarn that the dragon was taken to the Underdark, and while the kobolds were otherwise engaged, used Dust of Disappearance to hightail it out of there.
The lower level of the Citadel features passive skeleton gardeners tending to the Gulthias tree's spawn. The bugbear Balsag guards the entrance to the Underdark and another female but unnamed bugbear works alongside the gardeners elsewhere in the dungeon. The book tells us nothing about her, but it came clear enough to me that these bugbears know and care about each other.
The party bumped into a blight, drawing the ire of the skeletons and Balsag. During the fight, our cleric used Turn Undead which sent one of the gardeners panicking down the nearby hall, alerting a host of goblins and the second bugbear. We were faced with a long drawn out fight, so I had her arrive and demand a stop to the violence. Some tense conversation followed, but ultimately our Minotaur character with a black and white sense of justice equated the bugbear guarding the passage with involvement in slave trade and decided to start up the fight again. All throughout, female bugbear raged at them mourning Balsag, calling the party murderers and monsters. Although all I did was pause the combat to deliver dialogue, the party spent the aftermath trying to sort out about how to approach creatures just doing their thing. My theme is starting to take root.
Later in the dungeon there's a pair of Salamanders (swapped in from Fire Snakes). They exist in different rooms and have little description other than that they're there. They killed the first one without a thought. The second one though, they found resting in a nest and fell over themselves apologizing for the intrusion. They didn't dare mention their run in with first Salamander, and quickly put together what was going on and felt terribly for it. They're learning.
By this point my table is fully buying into this idea that factions of monsters aren't simplistic punching bags, and have their goals and reasons for being places. They've alerted Cryovain of Venomfang's plot and imagined the battle that must be happening fully off-screen. They're now rushing to return Calcryx to her with actual worry that she may be injured. The things at stake are ultimately more interesting than just monsters to fight.
Rewarding Curiosity
The best part of all this is that many of the plot points going on are things the players mused about and theorized casually 'how could these two things be connected', and as a DM I have the full power to just say Hell Yeah. Being creative and quick on the draw isn't the easiest, most natural thing for everyone. Luckily, when you're running a game you have a handful of other brains investing themselves in the world and coming up with ideas. Players will ask 'what happens if I do this' and very often the answer isn't right there for you in the printed adventure as-is. You could just say nothing happens and the moment falls flat, or you can let the players craft the world through their interactions. An example:
There's an out of the way chamber in the Sunless Citadel that holds an old tributary statue of the dragon Ashardalon. There's a collection plate in its mouth that seems to want something. As far as the book goes, that's it. No trap, no treasure, no reward for finding this place other than seeing a pretty statue. My table became very interested in this room and how it works. I couldn't let that opportunity slide by. They put a treasure on the collection plate, the statue glowed with a fire from within, and an ancient, distorted magic mouth spell proclaimed "Ashardalon accepts your gift". Then the head threw back like a pez dispenser and the treasure tumbled inward.
Well, the party decided, there must be more treasure to be had in there. They investigated the mechanisms of the statue, considered destroying it, and eventually decided to lower their kobold friend Meepo inside. They tied a rope around him and offered him to the statue, then lowered him. And lowered him. And it kept going until they were nearly out of rope. And then, a tiny faraway echo from deep within. "Shiny!" And then a rumble and a growl and panicked kobold noises. The party pulled him back up, mortified but with a handful of gemstones as a reward. He obviously took more than he'd let on, his pouch near bursting with his own treasure, but the party decided he deserved to keep it. Rolling with this player idea felt good for everyone at the table, introduced a tiny story to play out, and turned an otherwise nothing room into a memorable encounter.
What's Next
As my party nears the end of a story arc, I'm in the process of preparing more locations through chapters of multiple books. There's a lot more that happens nearby with Phandelver and Below and the Essentials Kit trilogy, but there's a want to travel to new regions, so these plots will likely continue on in the background, picking and choosing which locations and missions are interesting enough to surface. Storm King's Thunder gives plenty of life to the greater area, and the party's expressed interest in traveling south towards Waterdeep where we can cross paths with the story in progress from Tyranny of Dragons. I'm excited to see what the second act holds, and look forward to more surprises and twists as the world comes together before us.