OpenGameArt Sprites and License Questions

[Phantom]

http://opengameart.org/

I'm just curious about using opengameart sprites on a custom campaign, but if a sprite for example has a license for example Creative Commons by Share Alike, would that mean I have to release my entire campaign source files or just provide links and credit to the original author?

[Myran]

CC-BY-SA basically means that you can use it as long as you give credits and if you make changes to the sprite you must then also release your modified version under CC-BY-SA.
http://creativecommons.org/licenses/by-sa/3.0/

The most straight forward license is CC0, which means that the author has placed the work in the public domain, so you can use it for anything.
http://creativecommons.org/publicdomain/zero/1.0/