Difficulty Classes

Sometimes you need to quickly set a difficulty class. The easiest method is to select a simple DC from the Simple DCs table by estimating which proficiency rank best matches the task (that rank is usually not required to succeed at the task). If it's something pretty much anyone would have a decent chance at, use the untrained DC. If it would require a degree of training, use the DC listed for trained, expert, master, or legendary proficiency, as appropriate to the complexity of the task. For example, say a PC was trying to uncover the facts behind an infosphere rumor. You determine this requires a check to Recall Knowledge, and that only someone with master proficiency in Infosphere Lore would know the information, so you'd set the DC at 30—the simple master DC.

Simple DCs work well when you need a DC on the fly and there's no level associated with the task. They're most useful for skill checks. Because there isn't much gradation between the simple DCs, they don't work as well for hazards or combats where the PCs' lives are on the line; you're better off using level-based DCs for such challenges.

When you're determining a skill DC based on something that has a level, use the tables below to set the DC. Find the level of the subject, and assign the corresponding DC. Since spells use a 1–10 scale, use the Spell Rank table for them.

Use these DCs when a PC needs to Identify a Spell or Recall Knowledge about a creature, attempts to Earn Income by performing a task of a certain level, and so on. You can also use the level-based DCs for obstacles instead of assigning a simple DC. For example, you might determine that the walls of a space station were constructed of smooth metal and are hard to climb. You could simply say only someone with master proficiency could climb them and use the simple DC of 30. Or you might decide that the 15th-level mechanic villain who built the station crafted the wall and use the 15th-level DC of 34. Either approach is reasonable!

Note that PCs who invest in a skill become more likely to succeed at a DC of their level as they increase in level, and the listed DCs eventually pose very little challenge for them.

You might decide a DC should differ from the baseline, whether to account for PCs' areas of expertise or to represent the rarity of spells or items. A DC adjustment represents an essential difference in the difficulty of a task and applies to anyone attempting a specific check for it. Adjustments happen most often with tasks whose DCs are based on their level. You'll often apply the adjustments for uncommon, rare, or unique subjects.

The DC Adjustments table lists the categories of adjustments. The adjustments' names are relative to the base difficulty of the task itself—a very hard 2nd-level task will not be “very hard” for a 10th-level PC to accomplish! PCs who invest in a skill will become better and better at that skill as they increase in level. For example, even the best 1st-level PC has grim odds against an incredibly hard 1st-level DC, with a huge chance of critical failure, but by 20th level, an optimized character with a modicum of magic or assistance can take down incredibly hard 20th-level DCs over half the time, critically failing only on a 1. At higher levels, many groups will find that the very hard DC is more like standard for them; keep that in mind if you need a check that presents a true challenge to a high-level group.

You might use different DCs for a task based on the particular skill or statistic used for the check. Let's say your PCs encounter a magical tome about dragons. The tome is 4th-level and has the arcane trait, so you set the DC of an Arcana check to Identify the Magic to 19. As noted in Identify Magic, other magic-related skills can typically be used at a higher DC, so you might decide the check is very hard for a character using Occultism instead and set the DC at 24 for characters using that skill. If a character in your group had Physical Science Lore, you might determine that it would be easy or very easy for them to use that skill and adjust the DC to 17 or 14. These adjustments aren't taking the place of characters' bonuses, modifiers, and penalties—they are due to the applicability of the skills being used.

Sometimes succeeding at a particular task requires a character to have a specific proficiency rank in addition to a success at the check. Locks and traps often require a certain proficiency rank to successfully use the Pick a Lock or Disable a Device actions of Thievery. A character whose proficiency rank is lower than what's listed can attempt the check, but they can't succeed. You can apply similar minimum proficiencies to other tasks. You might decide, for example, that an electronic trap that uses a console requires training in Computers to understand. An untrained soldier can't succeed at the check, but she can attempt it if she wants!

For checks that require a minimum proficiency, keep the following guidelines in mind. A 2nd-level or lower task should almost never require expert proficiency, a 6th-level or lower task should almost never require master proficiency, and a 14th-level or lower task should almost never require legendary proficiency. If they did, no character of the appropriate level could succeed.

You as the GM set the DCs for certain checks or determine other parameters. Here are guidelines for the most common tasks. Remember that all of these are guidelines, and you can adjust them as necessary to suit the situation.