Knowledge
Key Ability: Int | Trained Only: Yes | Armor Check Penalty: No
You are educated in a field of study and can answer both simple and complex questions. Like the Craft, Language, Perform, and Profession skills, Knowledge actually encompasses a number of different specialties (called sub-skills). Below are listed typical fields of study.
- Arcana (ancient mysteries, magic traditions, arcane symbols, constructs, dragons, magical beasts)
- Dungeoneering (aberrations, caverns, oozes, spelunking)
- Engineering (buildings, aqueducts, bridges, fortifications)
- Geography (lands, terrain, climate, people)
- History (wars, colonies, migrations, founding of cities)
- Local (legends, personalities, inhabitants, laws, customs, traditions, humanoids)
- Nature (animals, fey, monstrous humanoids, plants, seasons and cycles, weather, vermin)
- Nobility (lineages, heraldry, personalities, royalty)
- Planes (the Inner Planes, the Outer Planes, the Astral Plane, the Ethereal Plane, outsiders, planar magic)
- Religion (gods and goddesses, mythic history, ecclesiastic tradition, holy symbols, undead)
Check: Answering a question within your field of study has a DC of 5-10 (for really easy questions close to one's lived experience), 15-20 (for basic questions in areas you have experienced), or 25 to 35 (for really tough questions related to knowledge entirely unfamiliar to you).
You can use this skill to identify monsters and their special powers or vulnerabilities. In general, the DC of such a check equals 10 + the monster's CR. For common monsters, such as goblins, the DC of this check equals 5 + the monster's CR. For particularly rare monsters, such as the tarrasque, the DC of this check equals 15 + the monster's CR, or more. A successful check reveals it is a monster and allows you to remember a bit of useful information about that monster. For every 5 points by which your check result exceeds the DC, you recall another piece of useful information. Many of the Knowledge skills have specific uses as noted on Table: Knowledge Skill DCs.
| Task | Knowledge Skill | DC |
|---|---|---|
| Identify auras while using detect magic | Arcana | 15 + spell level |
| Identify a spell effect that is in place | Arcana | 20 + spell level |
| Identify materials manufactured by magic | Arcana | 20 + spell level |
| Identify a spell that just targeted you | Arcana | 25 + spell level |
| Identify the spells cast using a specific material component | Arcana | 20 |
| Identify underground hazard | Dungeoneering | 15 + hazard's CR |
| Identify mineral, stone, or metal | Dungeoneering | 10 |
| Determine slope | Dungeoneering | 15 |
| Determine depth underground | Dungeoneering | 20 |
| Identify dangerous construction | Engineering | 10 |
| Determine a structure's style or age | Engineering | 15 |
| Determine a structure's weakness | Engineering | 20 |
| Identify a creature's ethnicity or accent | Geography | 10 |
| Recognize regional terrain features | Geography | 15 |
| Know location of nearest community or noteworthy site | Geography | 20 |
| Know recent or historically significant event | History | 10 |
| Determine approximate date of a specific event | History | 15 |
| Know obscure or ancient historical event | History | 20 |
| Know local laws, rulers, and popular locations | Local | 10 |
| Know a common rumor or local tradition | Local | 15 |
| Know hidden organizations, rulers, and locations | Local | 20 |
| Identify natural hazard | Nature | 15 + hazard's CR |
| Identify a common plant or animal | Nature | 10 |
| Identify unnatural weather phenomenon | Nature | 15 |
| Determine artificial nature of feature | Nature | 20 |
| Know current rulers and their symbols | Nobility | 10 |
| Know proper etiquette | Nobility | 15 |
| Know line of succession | Nobility | 20 |
| Know the names of the planes | Planes | 10 |
| Recognize current plane | Planes | 15 |
| Identify a creature's planar origin | Planes | 20 |
| Recognize a common deity's symbol or clergy | Religion | 10 |
| Know common mythology and tenets | Religion | 15 |
| Recognize an obscure deity's symbol or clergy | Religion | 20 |
| Identify a monster's abilities and weaknesses | Varies | 10 + monster's CR |
Note that Knowledge does not reveal information that you cannot know, that is outside your experience, study, or culture. You cannot use Know Arcana to reveal information about spells that have not been invented yet or whose inventor has kept secret. You cannot Know Nobility about the rulers of an unexplored land on whose shore you have just stepped. You cannot Know Geography or Local about places you have never been, read about, or even heard of.
Action: Pondering a question out of combat can take but a moment for an easy question, or up to a minute of thinking for tough ones. In combat, a standard action is suficient to answer most questions, though the game master may give a circumstance penalty of -1 or -2 for distractions. Identifying a monster's abilities in combat is a move action. A library is a tool you can use to assist in making knowledge checks, offering a circumstance bonus of +1 to +4, depending on the library; using a library increases the time required by 1d4 hours. A single book that is on the exact topic in question can act as a +1 library at the game master's discretion.
Try Again: No. The check represents what you know, and thinking about a topic a second time doesn't let you know something that you never learned in the first place. If you have a library at hand, you can try again.
Untrained: You cannot make an untrained Knowledge check with a DC higher than 10 unless you have access to a library.