Empire: A Reversed Engineer Game (2006)

From the introduction: In this land there are two great forces that govern everything, even the gods. Day is the drive to the exterior, to interact with the world outside of the mind in dynamic and novel ways. Night is the search inward, contemplating the mysteries that are hidden when looked at too closely. Day and Night exist more or less equally in all creatures, shaping their reactions and guiding them toward meaningful interaction with existence. No, not all creatures. The gods deal with Day and Night a bit differently. During the hours governed by the sun, they are completely ruled by their Day aspect; in the moon’s hours, their Night aspect gets free reign. What happens when such blindingly pure essences merge within a mortal, constantly swirling around but refusing to interact peacefully? That would be you, another one who the standard rules fail to cover.