Knowledge skill question

[Noedig]

My DM gave us an interesting situation to work with last game. The party and I are entertaining business relations with a group of planeshifting "business men" (glorified pirates) with a massive plane shifting ship.

They are mostly based in the Outlands but I think they should target the material plane more. I suggested this plan, but my DM ruled that I do not have high enough ranks to know what are in the the material planes other than my own (Faerun). What *specific* part of knowledge planes would be necessary to learn this information?

[ericgrau]

It's really up to the DM. But here's the rough guideline:

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).

Unless they are truly unknown to the world you should need at most a 30 on your knowledge roll. Maybe only 20.

[KillianHawkeye]

There are no "specific parts" to Knowledge skills. The DM sets the difficulty for your roll, and you either succeed or fail your check to determine whether or not you know the information. That's it.