At GenCon this year, I got a copy of the new Monster Manual. It’s a beautiful book, but one I opened nervously. I’ve never been good at using monster books. The monsters inside look cool, but I have always struggled with fitting them together in a campaign world. It’s been the biggest weakness in my ability to plan and run campaigns. I’m great for one-shots, but none of my campaign ideas really get off the ground. I am still very much a newbie DM, especially when it comes to worldbuilding.
While I read the newest Monster Manual, I could feel the monsters coming together in and around the world. There is easily digested lore for every monster in the main part of the book, and each snippet of lore has something a GM can sink their teeth into to turn into a piece of an adventure.
As I was reading, I was especially inspired by environment effects. Legendary monsters like dragons and liches affect the area around them, sometimes for miles. These involve animal behavior, weather patterns, ecologies, and more. Some effects linger after a monster dies, and some effects will be permanent.
Something about all of these monster effects made mapbuilding click in my mind in a way it hadn’t before, and I could start seeing monsters fit together like a puzzle.
Environmental effects make legendary monsters a “target” on a map. Place your dragon in the world and think about who congregates around her. Adding monster groups to the world and planning how they interact radiates out from a big bad guy. I grabbed some graph paper and tried it out, once with a green dragon and once with a kraken who had taken over a wizard’s tower in the middle of a lake.
The kraken was the monster I had the most fun reading. It’s a meanie in the new Monster Manual, and unlike what you might be used to about a sea monster, this one has the ability to breathe air and travel over land (while destroying everything in its path). So I decided to map out a kraken’s recent interest in a magic tower, and the repercussions that come out of that.
The kraken’s environmental effects are marked on the map, as well as its path of destruction where it walked on land from the ocean to the lake. After settling the kraken in, I started to add invested monster groups to the map. There is definitely room for far, far more in there.
I added some merfolk to the coast, who could be looking to bring the kraken back into its natural ecosystem. Some kuo-toa settlers are moving in near the lake, looking to take advantage of the ruins and damp ground to tunnel into. The other monster groups represent the existing communities the characters can be from and interact with.
As for the distances on the map, it’s pretty simple. The length of bracket, distance from legendary monster lair, and overlap with other brackets on page let you communicate monster group size, placement in interaction with other monsters on the map, respectively. This way you have interactions visually represented, rather than having the check notes or write a story ahead of time. For example, I know that something will happen involving the elven cities and the fishing villages, but I may be able to let the PCs build the details of that relationship for me.
As you’re building, you can add more legendary monsters and radiate their monster groups out, building richer interactions and making legendary monster Venn diagrams – perfect for a magical war scenario.
Big or small, I’m looking forward to using this quick world mapping technique and using it to add a depth to relationships and group interactions that I’ve struggled to incorporate into my game.