Today I'm talking specifically about the Knowledge skill, not about the concept of knowledge itself, which would involve much more time and effort than I can devote in a day. The Knowledge skill is a fantastic skill that I have seen entire parties spread their skill ranks into to make sure every one was maxed out by someone at all times.
Knowledge can be used in a general sense to determine what a character knows about a related field. For example: Knowledge Dungeoneering would allow someone to identify a mineral, or determine a slope. But you can also use Knowledge as a sort of Pokedex which the players can use to identify monster weaknesses, strengths, etc. I'll be honest I didn't even know that until about a year ago when a player pointed it out to me. Obviously I must have skimmed over that little bit in the book.
In relation to monster information, the actual rules on the subject are slim, explaining that a character knows its powers and weaknesses and not much else. While D&D gives the DC of a monster check as 10 + the monster's CR, Pathfinder scales it up or down by 5 based on the rarity of the creature. The books also state that more information is to be given per 5 that the DC is beaten by. What exactly is more information? How does one quantify this, and how much information is too much?
For the answer, I found an unofficial source for what information to give out. Now usually I'm reluctant to use unofficial or third party rules, (heck, I don't much like using anything besides core rules) but in this case, I felt it the best way to stay consistent with what the Knowledge skill provides. This way, my players always know what to expect based on their roll. The source I site is actually from a forum at the Wizards of the Coast community page called the Monster Lore Compendium. In the past, the exact information to give out when a player made a roll was vague, the compendium was comprised by a forum poster who went through almost every book available and actually wrote out what information was given by what roll. On the Pathfinder SRD, they actually integrated this amazing work into the monster pages themselves. Really fantastic stuff. As a source, I could not recommend anything more than I recommend this.
I'm running a bit behind today, as I've been very busy DMing a D&D 3.5 and a Pathfinder game every week, so I don't have much to say about the Knowledge skill, though I hope to go more in-depth with each skill eventually. Thank you for reading, and stay tuned tomorrow for "L is for Legend".
Monster Lore Compendium