I’ve run about 10 homebrew Pathfinder sessions now and I’m still trying to figure out how to build balanced and challenging encounters. The rule book covers adventures and encounters but seems to stop with details for groups that number over eight players. My main challenge is not only the number of PCs but also that my players are crafty as heck and work really well as a team.

As a result, I’ve adjusted the encounter creation rules a bit for my group. I’ve run these rules in the past and it seems to work fine, but this Saturday is our first game where I’ll really be testing this adaptation out. I thought I’d share the specs ahead of time for your input and for you to try in your own games.

The basic math looks like this:

Encounter Challenge Rating (CR) = Average player level (APL) + 1 per every 2 players at the table over 4.

Based on that, an encounter’s CR at my table looks like this:

3 (APL) + 2 (# of players over 4) = CR5.

At that stage, the CR abitrarily goes up +1 if it needs to be more challenging (ie: a boss battle or if the other challenges have been too easy), up to a max of the number of players at the table.

If I want to make an encounter more difficult, I’ll adjust it based on these tiers:

Easy CR = 4 (less than average)

Standard CR = 5

Challenging CR = 6

Difficult CR = 7

Epic CR = 8 (maximum is the # of players at the table)

Making the encounter

In each tier, I build the fight with 1 or 2 main adversaries/bosses and then pad it out with smaller enemies like goblins. Those “extra” enemies can show up over time if the fight is going too easy (or the PCs are rolling too well - or more appropriately, I’m rolling awfully) or not show up if the battle is going badly. That’s one of the great things about being the DM: no one else knows what your plan is for a particular fight so you can add and remove monsters from it whenever you want.

Once I figure out the math I want for each encounter, I’ll consult something like the Pathfinder Monster by CR chart/tool and combine a number of monsters that total the CR value for the encounter and call it a day.

After doing some testing with these numbers, my next challenge is determining the rhythm for all of the encounters in one dungeon or area.

Until now I’ve been lucky. In a dungeon with 10 rooms I might place 1 Epic, 2 Difficult, and 4 Standard match ups; enough to challenge the PCs but not enough to outright kill. I’m a n00b so I’m still finding my balance on longer-term dungeons or scenarios is murky water. I feel like there might be some kind of math formula I could make up for a sort of Total Encounter CR (TRC) that all the rooms/challenges could add up to.

Quickly, I’m thinking it could look like this:

TCR = 3x the number of players at the table

or

TCR = # of players at the table x APL

Mileage may vary depending on abilities of the PCs and how long you want to run the game for (ie: a megadungeon might not have a TCR because you’re in it all the time) or how much sweet magical loot you’ve given the group. And keep in mind that these are just super rough maths here - I’m still working out details and specifics.

Anyways, playing with math and making encounters. Hope this was helpful or gave you some insights into the sometimes maddening world of encounter design!

- Mathew out!