Do you know what an Adventure Path is? I’ll tell you, if you don’t already know. An Adventure Path is a series of adventures for a roleplaying game intended to guide adventurers from their humble beginnings to awesome greatness. It’s escalating threats concluding in a grand finale. It’s like a film trilogy you get to play.

So now that you know what an Adventure Path is, let’s talk about how an aspiring scenario writer makes one for a system like Fourth Edition Dungeons & Dragons. Fourth Edition is easier to write for than most because all the numbers scale easily across different levels and tiers of play.

Your starting goals need a form. Here’s one of the tried-and-true ways of looking at it: twelve months for twelve adventures to go from first level to thirtieth. It’s hard to keep a gaming group together when everyone has a life, so you want to make sure there’s a beginning, middle, and end, and that advancement is constant.

Thirty levels, divided by twelve adventures, is two-and-a-half levels per month, which means your characters should be “leveling up” every two to three game sessions. Sound fast? It can be. But it’s what you’re going to want to make your “deadline.”

How do you make an adventure advance the characters only two-and-a-half levels? That part is actually easier if you break adventures down into encounters. You’ll need an average of nine encounters per character level. You can range between eight and twelve, but nine is a good number. We’ll divide it up some more in a bit.

Plan for most of your adventures to be focused on not-combat. You can always improvise more combat encounters, but the non-combat stuff can be difficult to plan in advance, so you want to make sure you have the most of that. Plan for about six Skill Challenges to every three Combat Encounters per level. Sounds crazy?

Do it anyway.

Getting back to the nine encounters thing. If you need nine encounters per level, and you have thirty levels to cover (including those 30th-level endgame encounters), that’s two hundred seventy encounters to plan. It comes out to about twenty-two encounters per adventure. Make twenty-four instead because it’s safer that way.

If you have difficulty coming up with six Skill Challenges to three Combat Encounters, try instead to create eight Combat Encounters and then use the other sixteen Skill Challenge spots to get the characters from one fight to another.

You can group Combat Encounters and Skill Challenges together thematically, in groups of four to six. If you make “encounter clusters” of five using that pentagon method I blogged about years ago, you’ll even wind up with an extra encounter for your trouble. You can never have too many planned encounters.

When in doubt, you can skip over the extra encounter. Make shortcuts.

So you’re creating between twenty and twenty-five encounters to be played out over the course of a month’s adventuring. If you can devise ways to tie all the clusters of a given adventure together thematically, so much the better. Your adventures should all be a healthy mix of Skill Challenges and Combat Encounters.

Now you know the basic math, and knowing is half the battle.