The creator gods are all gods that sprang into existence out of nothingness. They are above everything and older than anything. These gods created the world, intentional or otherwise, along with its natural laws. Unlike the other gods they are unbound rules and are free to do whatever they want.
However, they do respect Nuada, the king of gods, who came after them and showed great wisdom. As such, they mostly follow the laws he made as a sign of appreciation.