You’re thumbing through your copy of Candlekeep Mysteries, and your DM brain is starting to feel gears click into place. Already you imagine how you’ll present certain NPCs, the way you’ll milk the suspense of discovery for your players. There’s just one problem. You’re already deep into a campaign set in Wildemount, and there’s just no room in your schedule to run another game. 

But suddenly, a burst of inspiration. Candlekeep is a massive library amassing knowledge from throughout the world. But, wait, there’s a massive, knowledge-thirsty library in Wildemount, the Cobalt Soul! So instead of waiting for a whole new campaign, why not just send this current crew to the archives in Zadash to uncover the secrets of a strange book with a mirror on it à la The Price of Beauty? Congratulations, you are now on your way to creating a D&D sourcebook mashup.

• Why Mash-up?
• How to Start Mashing-Up
• Examples of Mashups

Why Mash-up?

It can be easy to look at a published adventure book and think of it as having a locked-in story. But, a lot of fun can be had by mixing and matching adventures with the same modularity as optional rules found in a sourcebook like Xanathar’s Guide to Everything. This practice of mashing D&D books together can be an excellent way to achieve the versatility of a homebrewed campaign, with the guided hand that makes using published adventures so appealing. 

On top of providing additional versatility, experimenting with sourcebook mashups can allow for breaks in the campaign’s main story arc, thereby creating a player-driven sandbox campaign. There are plenty of one-shot-style adventures that can be pulled from other sources and used as side quests, which can be a lifesaver if you aren’t the kind of DM who has a bunch of different story threads prepped and ready to go.

Mashups also serve as a way of surprising players. A party who has built characters for a Strixhaven-based campaign likely won’t be expecting a storyline pulled from Waterdeep: Dragon Heist in which they need to investigate the cause of a murder on campus. With just a little imagination, you can keep your party on their toes with storylines from various worlds without them even knowing!

How to Start Mashing-Up

When looking for sourcebooks to mashup, it’s best to start small. Reskinning an entire adventure to fit the backdrop of your current campaign can sometimes require more work than simply writing your own plot. By this logic, it’s easiest to add content to your existing campaign that is already self-contained. Dungeons, being self-contained by nature, are the best example of this. For instance, if your party is heading for a temple devoted to a particularly evil deity, the Betrayer’s Rise dungeon crawl in Critical Role: Call of the Netherdeep is a perfect source of vile ideas.

Once you’ve successfully mashed up self-contained content, you can start looking for content that might take more legwork to fit into your campaign. These instances take more reworking than self-contained content but can provide huge payoffs when it results in multiple sessions worth of prewritten material. We cover some examples of more advanced mashups in this article’s Examples of Mashups section. Before we get to that, let’s discuss some elements to look out for when deciding to combine prewritten content from sourcebooks with a campaign you’re running:

• Mood: Does the setting you’re pulling inspiration from fit the mood or vibe of the adventure you’re already running? Is there a particular region or city in that setting you feel could substitute or be used in addition to your current locations?
• Characters: Are there characters or organizations that can work in your current setting? How would they fit into your current campaign, and what existing characters or organizations would be impacted by their inclusion?
• Antagonists: How do the creatures from the new setting fit into your current campaign? How much will you have to change their lore and game statistic to make them work?
• Stakes: One of the major challenges when bringing a story to a new setting is making sure the stakes don’t get lowered in the translation. For example, the adventure in Baldur’s Gate: Descent into Avernus might not feel as intense if removed from the fiery wasteland of the Nine Hells. Similarly, removing Curse of Strahd from Barovia might make it feel decidedly different than a typical Strahd game. Both may be rewarding challenges if you feel like accepting them, however.

Examples of Mashups

With some exceptions, most of D&D’s most popular adventures can be moved to other settings and fit fairly seamlessly. Here are just a few examples of some settings and adventures that could be easily tossed together for a campaign:

Waterdeep: Dragon Heist and Guildmaster’s Guide to Ravnica: The planet-sprawling megacity vibe of Ravnica combined with the built-in faction intrigue of the city’s ten guilds layers perfectly with the urban vibe of this treasure hunt story. Any of the four possible villains in Dragon Heist could be rewritten as a member of a guild or could be replaced with an important guild dignitary from the world of Ravnica.

Storm King’s Thunder and Mythic Odysseys of Theros: The Ancient Greece-inspired world of Theros was once ruled by primordial titans who were overcome by the current pantheon of gods. Some of these titans rising up could easily take the place of the giants of your Storm King’s Thunder campaign. The world of Theros is smaller than Faerun, but there are still plenty of areas to make your players explore before the end of the campaign.

Lost Mine of Phandelver and Wayfinder’s Guide to Eberron: This mashup can work well if you want to use the Starter Kit adventure to introduce new players to D&D, but you also know your group would have more fun in the world of Eberron. You can simply place the small town somewhere in Khorvaire, adjust the history of the mine so that it was lost during the Last War, and pepper in some of the setting’s dragonmarked houses or introduce a group patron as you play. Then, once they’ve defeated the Black Spider, you can continue the story into other areas of the world. 

Icewind Dale: Rime of the Frostmaiden and Explorer’s Guide to Wildemount: The Biting North, made up of the Greying Wildlands and the frozen region of Eiselcross, could serve as a fitting setting for the brutal survival horror adventures. The ruins of the pre-Calamity city of Aeor sub in well for the remote locations and story hooks of Rime of the Frostmaiden.

Ghosts of Saltmarsh and Baldur’s Gate: Descent into Avernus: You can even mashup two different adventure books. While Descent into Avernus is a self-contained adventure, it also provides DMs with a plethora of locations for characters to explore. Replacing Saltmarsh’s seafaring setting and vessels with the open wasteland and infernal machines of Avernus could give you a vast branch of new tales to tell in the Nine Hells. Likewise, you could do the exact opposite and turn the wasteland of Avernus into an ocean-sprawling pirate-war or lost-at-sea Odyssey-like adventure. It would have such a different vibe that your players might not even know what inspired it. 

Let’s Get Mashing!

We hope this article has inspired you to try a mashup of your own! The examples provided are just a taste of ways that you can combine a pair of sourcebooks to tell a different kind of story. Hopefully, this gentle nudge can help you get the ball rolling to try something similar—or even more off the wall—in your own games. 

Riley Silverman (@rileyjsilverman) is a contributing writer to D&D Beyond, Nerdist, and SYFY Wire. She DMs the Theros-set Dice Ex Machina for the Saving Throw Show, and has been a player on the Wizards of the Coast-sponsored The Broken Pact. Riley also played as Braga in the official tabletop adaptation of the Rat Queens comic for HyperRPG, and currently plays as The Doctor on the Doctor Who RPG podcast The Game of Rassilon. She currently lives in Los Angeles.