Source is a type of magic, the nature of which was up for debate in Divine Divinity (some thinking it was a lesser form of deity, most an extra-dimensional energy field). It was originally discovered and used for healing, but something corrupted it, causing it to possibly corrupt those using it. Source magic was forbidden during D:OS and outlawed during D:OS 2, as well, though in response to the voidwoken (just before D:OS 2, source users had fought along side the Divine Order against the Black Ring).
