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Skills

Skills represent some of the most basic and yet most fundamental abilities your character possesses. As your character advances in level, he can gain new skills and improve his existing skills dramatically.

Knowledge (Int; Trained Only)

Source PRPG Core Rulebook pg. 99
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)

Check: 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).

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. Many of the Knowledge skills have specific uses as noted on the below table.

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

Action: Usually none. In most cases, a Knowledge check doesn’t take an action (but see "Untrained," below).

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.

Untrained: 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.

Phrenology (Arcana)

Source Occult Adventures pg. 196
You examine the skulls of intelligent creatures to analyze the subjects’ psychological attributes, since the shape of the brain influences the shape of the skull.

Check: Once per day, you can use your fingertips to examine the shape of a creature’s skull. Reading a creature’s skull requires 1 minute of concentration and scrutiny while you physically manipulate the skull. This technique can be used on a willing, helpless, or paralyzed creature, or on decomposed remains (as long as the skull is intact or can be pieced together). This skill can’t be used on creatures without discernible skulls, such as constructs, elementals, oozes, or plants. After the minute is up, the GM attempts a secret Knowledge (arcana) check. The DC is typically modified by the subject’s Hit Dice. With a single check, you determine all the information whose DC you meet. For instance, if you had a result of 22 when examining a creature with 2 HD, you would learn that creature’s race and age, gender, alignment, and class, but not its level or HD.

Task	DC
Determine race and age	10
Determine gender	15
Determine alignment	15 + creature’s HD^†
Determine class	20 + creature’s HD^†
Determine level or HD	25 + creature’s HD^†

^{† A dead creature’s skull uses the HD the creature had when alive.}

Action: Reading a creature’s cranium requires 1 minute of uninterrupted study.

Try Again: Yes. Reexamining a skull may provide new insights. You can attempt only one such check per day.

Occult Skill Unlocks

Characters capable of casting psychic spells or who have the Psychic Sensitivity feat gain access to skill unlocks—a host of esoteric skill uses not available to other PCs. These are not entirely new skills, but rather new uses of existing skills for those trained in the occult arts. A character must be trained in the appropriate skill to use that skill’s unlock, even if the skill can normally be used untrained. It’s impossible to take 10 for an occult skill unlock. Occult skill unlocks require intense concentration and strenuous effort, so the amount a character can use each skill unlock is limited to once per day or per week. This limit is for all uses of the skill unlock; if a character uses hypnotism to implant a suggestion, he can’t also use it to recall memories on the same day.

Recall Intrigues

Source Spymaster's Handbook pg. 9
You can identify feats and the class features of various classes with successful Knowledge checks when you observe the feats or class features being used.

Check: You can attempt a skill check to identify a feat or class feature when you observe it in use, similar to how Spellcraft can be used to identify a spell. The feat or class feature must have some observable effect in order for you to attempt the Knowledge check. For example, you can’t see the internal determination of Iron Will, so this ability can’t identify that feat. In general, if a feat or class feature creates a noticeable effect (such as the extra attack from using Cleave) or has a variable modifier a character must choose to use (such as Arcane Strike, Combat Expertise, or Enlarge Spell), it can be identified. If it creates a static bonus (such as Dodge or Lightning Reflexes), there’s no telltale sign to give it away.

The Knowledge skill required to identify a feat or class feature varies depending on the type of feat or class feature to be identified and is outlined in the table below, along with the DCs of such skill checks.

Task	Knowledge Skill	DC
Identify a class feature from a class that grants arcane or psychic spells	Arcana	10 + class level when feature is granted*
Identify a class feature from a class with access to the druid or ranger spell list	Nature	10 + class level when feature is granted*
Identify a class feature from another class that grants divine spells	Religion	10 + class level when feature is granted*
Identify a class feature from any other class	Local	10 + class level when feature is granted*
Identify a combat feat being used	Local	10 + character’s level
Identify a metamagic feat being used	Arcana	10 + character’s level
Identify a teamwork feat being used	Nobility	10 + character’s level
Identify any other feat being used	Local	15 + character’s level

^{* Add 10 to the DC if the class is a prestige class.}

Researching Technology

Source Technology Guide pg. 5
A character can use the following skills to research technological subjects. Other skills may have research applications as well, subject to GM approval.

Heal: Used to identify and understand pharmaceuticals.

Knowledge (arcana): Although robots are constructs, Knowledge (arcana) cannot be used to identify robots or their abilities and weaknesses.

Knowledge (engineering): This is the most important skill with regard to technological subjects. Knowledge (engineering) can be used to identify a robot’s abilities and weaknesses. Knowledge (engineering) is also used to identify and understand unknown technological objects in a similar manner to how Spellcraft is used to identify the properties of a magic item. The DC to correctly identify and understand an unknown technological object is equal to the object’s Craft DC. An object with a Craft DC of 15 or less can be automatically identified and understood by someone trained in Knowledge (engineering) who also has the Technologist feat.

Knowledge (geography): Used for astronomy.

Unchained - Skill Unlock

Source Pathfinder Unchained pg. 85
With sufficient ranks in Knowledge, you earn the following.

5 Ranks: When you successfully identify a creature, you gain one additional piece of information for every 5 ranks you possess in that Knowledge skill.

10 Ranks: When you successfully identify a creature, you gain a +1 competence bonus on attack rolls, opposed ability checks, skill checks, and caster level checks against creatures of that kind (e.g., glabrezu demons, but not other demons or evil outsiders) for 1 minute. This bonus increases by 1 for every 5 ranks beyond 10 you possess in that Knowledge skill.

15 Ranks: When you fail a Knowledge check, you can reroll the check at a –10 penalty. The competence bonus above also applies to saving throws against exceptional, spell-like, or supernatural abilities used by creatures you identify.

20 Ranks: Whenever you attempt a Knowledge check, you can roll twice and take the better result.