If you're trained in this skill, you are educated in a field of study and can answer both simple and complex questions. Like the Craft, Perform, and Profession skills, Knowledge actually encompasses a number of different specialties. 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)
Knowledge checks don't take an action, and you can't retry a Knowledge check. 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.
You cannot make an untrained Knowledge check with a DC higher than 10. If you have access to an extensive library that covers a specific skill, this limit is removed. The time to make checks using a library, however, increases to 1d4 hours. Particularly complete libraries might even grant a bonus on Knowledge checks in the fields that they cover.
| Knowledge task | Requires | Time | Retry | DC |
|---|---|---|---|---|
| Answer question | --- | --- | No | 10 or more |
| Identify common monster | --- | --- | No | 5 + monster's CR |
| Identify uncommon monster | --- | --- | No | 10 + monster's CR |
| Identify rare monster | --- | --- | No | 15 + monster's CR |
Answer Question: Answering a question within your field of study has a DC of 10 (for really easy questions), 15 (for basic questions), or 20 to 30 (for really tough questions).
Identify Monster: 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 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.