New content created by me or paid for to develop this game (including all art and the locale of the Splintered Realm) are released under an Attribution Share-Alike Creative Commons License. You are free to take, re-mix, and re-use all original content herein, as long as you give credit back to the source.
The core game engine and its mechanics are released under the Open Game License (see page 119).
In short, the Splintered Realm is now your playground. Have fun in it!