I’m going to share with you something which might shake you to your very core: when playing Dungeons and Dragons, you can steal from whatever books you like. Think further than Tolkien, and much further than the core rulebooks. Unless intellectual property lawyers have infiltrated your party, you have free reign over all books, comics, and music ever written. (On the off chance that Tom, who sometimes wears a tie to games, is an undercover operative from the Random House legal team, I think you may well get off lightly.)
Published adventures especially need some variation from what’s in the book, to stop them being single-serving stories. There’s no reason why you can’t play Lost Mines once a year, so long as you have added something interesting.
When people like Matt Colville say to just read the first and last chapters of a published adventure and then do what you like with the middle, or Chris Perkins tells you to make the adventure your own, they’re not suggesting you do that within the rigid confines of Forgotten Realms. They mean go and liberally steal, add a saucy twist, and run with it. There’s no need for your sauce to be homemade either.
I just finished reading Terry Pratchett’s The Colour of Magic and have come away with too many ideas to fit into a once-a-week D&D game. Every wizard and his familiar has a bag of holding in Forgotten Realms. Your players are heroes they deserve a sapient pearwood trunk, which they found trapped at the bottom of a cave system, sitting loyally by its late owner. Once they’ve found out how to befriend it, think of the fun they’ll have watching scoundrels lose their fingers. Think of the jealous wizards who recognise the distinctive dark rings.
Spice up your death saving throws by having Death sitting next to the adventurer once they become unconscious, patiently waiting (or not so patiently) for that critical failure. Whilst He’s there your warlock with truesight spots him and has a bit of a chat, revealing a clue that might set up the rest of the campaign. What if this was the only state which you could communicate with Death in, and your players start an odd death cult just for these nice get-togethers.
Don’t let cats be boring cats when you can steal straight from JK Rowling and make them Kneazles. No good detective should be without one, considering their ability to detect truths and lies. Instead of lockpicks, give your forest gnome rogue a Bowtruckle, the adorable and sensitive stick insect-like creature from Fantastic Beasts. There’s no need to change any game mechanic when doing this – maybe instead of proficiency with the lock picking tool, the player can use their animal handling.
Reskin Find Familiar as Find Dæmon for a select few people who live in a recently discovered distant land. Oh, and how interesting, the special connection between the person and the dæmon can be harvested somehow. Just plain rip off Philip Pullman’s Northern Lights and make it into a campaign. Your players will be both excited to play in a world they know, and curious to see which bits you’ve changed.
Swap out your big bad cultist or power crazed wizard for a young girl who’s just discovered her mighty telekinetic powers who’s causing a rather significant amount of bother. Set in the middle of the events of Carrie (Stephen King), how will your murder hobos handle subduing a budding woman when they understand her complex motivations. Surely they’ll have more of a dilemma than merely fighting Krad the Cruel, the latest monster of the week.
Run with a simple idea like the recent discovery of magic which allows you to carve a beautiful marble dragon, slowly leaking your soul into it, bringing it to life fantastically and powerfully. Check out the Assassin’s series by Robin Hobb to find out how that works out.
The lesson you should take away today is that anything is up for grabs. Don’t stick with fantasy. It’s possible your players will cotton on to what you’re doing very quickly, but in my experience, that’s never diminished the game. Being in an already fleshed out world only makes the whole scenario more real. The ideas are already out there; all you need to do is remix them a little.