Originally Posted by knc1
It is against site police (guidelines, section 8) to post direct links to copyrighted materials.
There might be two or three ones that I lost track of (I'll review all of them in spare time) and one with screenshot from the game, but most of them were fan-made and released on liberal licenses. My entirely own ones (Sówka and Super Derpy) are under CC-BY-SA 3.0. I'll try to provide list of sources and licenses together with the pack and remove anything that exceeds fair use, but well, I tried to think about it when creating them so it may be that nothing will need to be removed at all.
But I think that's slightly offtopic.