How to Write a D&D Campaign
Long-term play is fun, but it certainly takes some work from the Dungeon Master, especially if you are not running a published Adventure Path. It is also a gratifying thing to pull off.
This is how I design my home campaigns, which usually run for three to five years in real-time.
Start with the Endgame & Statblock
Whether it’s saving the kingdom, bringing down the government, or defeating a major devil on its own turf, it pays to know what you are working towards. Once you have that, you can begin fleshing out the details and tone.
Along with the endgame, get an idea of what your prominent Big Boss at the end will be. Their motivations can give you an endless array of plot hooks giving the overall campaign a consistent "feel."
Always remember that no one is the villain in their own story. Your Big Bad Guy usually sees himself as a hero or crusader. (Ronan The Accuser in the first Guardians of the Galaxy movie is a terrific example of this.)
I've always been fond of creating a statblock for the campaign as though it were a creature combatant. This not only lays out the fundamentals of the game but also gives you a nice condensed way to explain the campaign to potential players.
Here is the format that I currently use. Each bold section should get one to two sentences worth of text. Keep it short because all of this will be expanding rapidly. This is also valuable information to present at your zero session.
Campaign Statblock
System - What game will you be playing? Pathfinder 2, D&D 5e, GURPS, Savage Worlds, Dr Who, etc.
Where and when do we play? Day, time and frequency (i.e. every other Thurs at 7pm). Online or in person?
Continuity - Are the sessions episodic? Large arcs? Combination?
Rating - I use movie ratings. Everyone knows them. Anything PG-13 or more, and I note adult content here.
Style - Is the game focused on exploration? Social (investigation, political, etc), action? Heavy or light combat?
Tone - This is an important one, and one that tends to evolve a bit over the course of play. Is it going to be grimdark, action comedy, cartoonish, drama, etc. I like to think of it in terms of a movie soundtrack. Would the theme music be Carmina Burana or the Monty Python theme music? (Beware the Macarena.)
Scope- How far will the story range? Is it a Small town horror story? A multiversal epic? A journey to the center of your mind? Somewhere between?
Tablets, phones, and digital tools - Are they permitted, encouraged, or banned? Do you use online tools like Obsidian Portal or Roll20?
Characters
Starting level - Many campaigns do not kick off at first level. Some people like to have a little more punch at their disposal, and some DMs like to get right to the larger challenges.
You can even see this in published products. For example, in Spelljammer 5e, characters are supposed to start at the 5th level. In AD&D's Dark Sun, PCs started at 3rd level.
Background - Are the PCs from an established campaign world? Are they from distinctly separate cultures? Are PCs allowed from multiple existing settings (most of my games are planar in nature, so this is my personal default).
Downtime - How will downtime and associated events (magic item creation, etc.) be handled? Before or after a regular session? Between games via email / Forums / Discord? Etc?
Rules
Rule Zero - Is it in play or not?
Rules Variance - If using any custom rules changes (ignore encumbrance being the most popular) or additional subsystems are allowed. You don't need to put more than "Extensive House Rules"
Outside Sources - This is not only where you list any non-core books that are in play but is also where you would make note of it if you are willing to review prospective new sources submitted by your players.
Firearms - Do they exist in your game? If so, to what extent? In games like Pathfinder 1e, I will generally denote the level of firearms here, ranging from emerging to commonplace
Psionics - Some love ‘em, some hate ‘em. Either way, it's always good to know upfront if they're part of the program.
The Big Pieces
The idea is to start large and rough, adding more detail as needed. A few sentences each is a good starting point. Google Docs, wikis, and dedicated game platforms like Obsidian Portal, Scabbard, and World Anvil are excellent for keeping this stuff organized while allowing for easy expansion as details are developed.
It's important to note that you do not need to detail everything. It is one of the most commonly heard DM complaints that "I put in all this work, and the party will never see it because they went the other way."
A few sentences here and there are good. Save your energy for focusing on the next things the PCs will encounter. If they go off the map, take notes (see Improv below). If they don't, you have saved time that can be used devising even more fiendish encounters.
Recurring Themes
It is not merely the setting you choose that gives a campaign its individual feel. Think about the overall theme and the natural conflicts that come out of it. I like Law vs. Chaos like Michael Moorcock in his Eternal Champion novels.
For some, a black-and-white Good vs. Evil conflict is the theme. Exploration games bring the Danger of The Unknown and survival scenarios Triumph Over Adversity. Once you have these in mind, you can use them to add more flavor to the rest of your campaign design and plot hook creation.
This is also where I usually take note of any great, overarching secrets that are integral to the campaign. If you're running an intrigue-heavy game, I'd advise breaking those secrets out into their own subsection.
Major Cultures/Nations
For major cultures and nations, you just need the basics of the culture in which adventures will be taking place. Is it all western European analogs?
Do significant portions of the action take them to other cultures, like the ones presented in Beyond The Radiant Citadel? Is it confined to one plane of existence?
For example, if I were running a Forgotten Realms game that ventures into Mulhorrand for some good Egyptian-style adventuring, I would note both. If it is a homebrew setting, I'd start with a few sentences on each culture involved.
Pro tip: while a fleshed-out world is great, limit these to just the areas where the action will take place.
The Map
When you've figured out your basic nations (or star systems, multiverses, etc as appropriate), you might want to start making a general map of the campaign area.
If you're using a homebrew world, develop some geography-based challenges in the prime adventuring areas.
Major Factions
This includes churches, cults, secret societies, political groups, and more. Factions are another layer of potential conflicts and hooks, especially if any player characters are members.
If you are creating them from scratch, consider their scope. A major faction in a single nation has far less reach than a minor faction that stretches across multiple planes.
Major NPCs
Now that you have a basic idea of your endgame, themes, nations, and factions, you can sketch out some of your major NPCs.
Write a paragraph or two each describing low, mid, and high-level bosses and other notables from the cultures and factions you developed.
Stats can come later. Right now, you're creating a focused outline.
Major Events
These can be major campaign milestones, or they can be background situations that affect the setting. To use an example from Greyhawk, surviving a dungeon would be an example of the former, while the ongoing war in the Empire of Iuz would exemplify the latter.
Get a good idea of how you want to set up the big final battle. It can be as simple as "face off against the avatar of Demogorgon in a massive dwarven foundry." Then consider what steps would take the PCs to the encounter.
Using the example above, there will obviously be dwarves and dwarven lore involved at some point. It also points to Underdark adventures and the ones above ground that lead them below the earth.
Think about how the different cultures and factions you created might be involved. Continuing our example, a good-aligned church would have issues with a Demogorgon.
A clan of Derro in the Underdark that hate the Dwarves might aid the PCs. The discovery of a secret demon worshiper in the town's clergy leads our heroes to the Underdark, etc. Consider the possibility of the PCs getting caught between two or more groups.
Now you have a solid, basic, god-like view of the terrain ahead and can develop increasingly granular levels of detail where desired. Look for obvious friction points between your factions, cultures, and the player characters. This is where your encounters come from. Try to have one of these events as part of each session. The Campaign Template is a useful tool for planning individual sessions.
The Vital Importance of Plan B
Now that you have your rough list of events and conflicts start working on some alternative encounters that will advance the story for those times that your original plan gets overlooked or bypassed (which it will).
Let's take a look at some tools and techniques for making life easier as you settle in for the long adventure.
Session Zero
Keep in mind that you might be adjusting things a bit after you have your Session Zero. I view these as being essential for the comfort and enjoyment of all at the table.
Steal From Media
When considering how to create a D&D adventure, meaning a single session in a campaign, pilfer from your favorite shows.
Look at the story beats as the story progresses. These can be helpful patterns to use at the table.
Think about ways to steer things towards a cliffhanger at the session's end. "See you next week! Same Bat Time, Same Bat-channel!"
For a more in-depth discussion of story beats and adapting them to the game table, check out our episode How to Bring Storytelling Elements Into D&D.
Media can also be a great source of ideas for subplots, NPCs, and settings. Just remember that if it is a classic, your players probably know it as well.
Adapt, Re-Skin, Collage
There is a lot that you can do to expedite things if you're a new DM or are short of time. The wealth of pre-published material that is a gold mine for the time-pressed DM. Make use of it.
A creature here, an encounter room there, and the odd NPC are all easily used as they are in many cases. A useful statblock is useful regardless of its label.
Never underestimate the value of re-skinning existing creature opponents or rules elements to fit the atmosphere you're creating. It is such a useful tactic that we devoted an entire episode of the +1 To Gaming podcast to the idea.
Improv and Take Notes
It never fails. The PCs will go way off the projected path following some tiny detail they've become obsessed with.
This is where the ability to improv and having decent notes or a wiki is insanely useful. If you have rough notes on the area they are venturing into then you can extrapolate as you go.
Just make sure to take notes on what you're coming up with for when the PCs return. (They always seem to return.) Using NPCs as an example, jot down the name, species, any notable characteristics, and the nature of their interaction with the party.
This also helps you create an ongoing cast of characters that can appear later in the campaign, providing a sense of continuity.
Player Agency and Investment
Nothing takes a player out of the game more than a lack of agency. If the player feels their decisions don't matter, they will not enjoy playing.
Likewise, if they do not have a connection to the setting, they will also often fail to enjoy themselves. I view these as the two biggest dangers to a long-running game.
Just Say Yes
The PCs bring you a crazy, overblown, outright insane idea and your first impulse is to say no. Ignore that impulse. People play these games to do crazy things and experience wild situations.
Instead of "No, but.." make your answer "Yes, but it won't be easy." Let them know their chances are slim and make the die roll a hard one ("Sure, if you can roll 00 on percentile dice"), but let them try. When they succeed, it will be memorable, and if they fail (as is likely), the DM can have a field day with the aftermath.
If they want to go off the map, refer to my words on the subject of improv. Don't say no. Let them - and take notes. Not only does this preserve player agency, but whether the crazy idea succeeds or fails, it should provide a thoroughly entertaining session.
Tie Your Players to the Settiing
To get your players invested in your game, integrate them tightly into the setting. Why are the PCs adventuring together? Are they sponsored by one of the nations, a letter of marque in a pirate game, for example, or by one of the factions? Do any of them have relatives in one of the factions? Think of all the ways in which to ground them in your world.
Family is a great way to do this, but it is also one that many players are rightfully wary of. In metagaming terms, most players see them as potential hostages.
While that can occasionally be useful, family connections can be used in a lot of ways. Perhaps a wealthy relative is sponsoring their missions or acting at cross purposes. Think about how crazy many real-life families are and carry that over.
Now, Time to Write Your D&D Campaign!
So from a fellow campaign writer, that's my guide to writing a d&d campaign. I hope that you found it useful!
I'd like to end by reminding DMs that, at their best, RPGs are collaborative storytelling. Give your players some room to create and have a hand in the world; the rewards will be great! In the words of Dr. Seuss, "Oh, the places you'll go!"
Don't be afraid of the DM's chair. You'll be surprised at how rapidly you grow at ease with it. The world always needs more DMs!
May your 20s be both natural and frequent!
- George "Loki" Williams
PS: If this article has been helpful you might want to look at these associated resources: First Time DM Tricks, Collaborative Worldbuilding Tips for DnD, and How To Improve D&D Combat Encounters.