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Pathfinder RPG (2nd Edition) Pathfinder RPG (1st Edition) Starfinder RPG

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GameMastery Guide / Running a Game / How to Run a Game / The Science of GMing / Building Encounters

High- and Low-CR Encounters

Source GameMastery Guide pg. 41
The game expects that for about half of the encounters the PCs face, the CR of the encounter is equal to the average party level (APL). Obviously the rest of the encounters are higher or lower than the average party level, but what is too low or too high?

Table 12–1: Encounter Design only covers encounters from APL –1 to APL +3, so that CR range is the usual limit for most encounters. After all, for a party of four 6th-level PCs, an “easy” encounter (APL –1) is a “rival” group of four 2ndlevel NPCs (CR 1 each, +4 for 4 creatures = CR 5); if beating up NPCs one-third your level is easy, beating up even weaker creatures is more like bullying than adventuring. The risk of using very easy encounters is that the players may grow bored—they know their characters can deal with the monsters, but have to go through the motions of making attack and damage rolls without the excitement or risk from a “real” encounter. (Much like a “god mode” setting in a video game, the novelty of easily destroying all opponents gets old after a few encounters.) In some cases it’s acceptable or even a good idea to lead off an adventure with a very easy encounter—for example, if the players need a morale boost or have power-boosting abilities that require some kills to start functioning—but in most cases you don’t want to create encounters below APL –1.

The value of APL +3 should be a fairly hard limit for difficult encounters unless you want there to be a considerable risk of PC death. Once you’re beyond APL +3, the PCs’ ability to pose a threat to a monster dwindles, especially if the encounter is a single powerful creature rather than multiple ones on par with the APL. In most cases, this is because using a higher-CR monster may cross one of the invisible “break points” in monster design where the creature’s defenses and abilities assume the PCs are a certain level and have access to certain spells or gear, such as magic weapons, spells to remove ability damage, items neutralizing poisons or disease, or even simple things like being able to hit the monster’s AC or meet its saving throw DCs. If the PCs lack a critical spell or piece of gear, a difficult encounter may be nearly impossible.

For example, a succubus is a CR 7 encounter, and is an “epic” encounter for a group of four 4th-level PCs. Most PCs at that level lack cold iron or good weapons, and thus have to deal with the demon’s DR for every attack. The PCs may have difficulty overcoming her SR 18, energy resistances, and immunities, thus spellcasters will be frustrated. The PCs have even odds at best of resisting her at-will charm monster and suggestion (usually taking one PC out of the fight), and have to work very hard to make up for the temporary hit points from her at-will 6d6 vampiric touch.

It’s entirely possible to have an exciting and challenging fight (CR equal to APL +1 or +2) without overwhelming the PCs. An “epic” fight may last two or three hours of real time—a memorable fight if the PCs win, but a depressing slog if they can’t. It’s generally better to keep combat encounters to about an hour—that way you can get two or three encounters into one night of gaming, and make more progress in the adventure or campaign than a single, longer fight. If the fight you’ve given the PCs ends up too tough for them, don’t forget to remind them that they can run away, or you can cheat a little bit and suddenly treat the monster as if it had the young creature template (–2 on all rolls), which might be enough to turn the tide in the PCs’ favor—after all, you want the PCs to win, because that means everyone gets to keep playing. Killing them with an accidentally-too-hard encounter is no fun for anyone.