In fantasy, particularly romanticised and high fantasy, few authors tend to discuss what in their universe, is the function or origin of time. i feel many do the understandable relation of simply saying time is just as mysterious as in our own world, but ive always liked to use Fantasy as a place where i can make sense of anything as i myself dictate the laws and fundamental properties of the environment, and as such ive made Time a almost primordial force that has some unconscious omnipresent will off its own. for example the "creator" figure in my Mythos is the great flame Allunas, he created life and the world of Aphal, but even he was willed into existence, nothing simply "can be" and Time has this certain impulse to allow the properties so that even in nothingness, something will happen. thats always how ive used it at any rate, a force so pervasive and interwoven yet by no means actually a living embodiment. i could go into more detail about how ive staged the 3 existing dimensions of Aphal and how they each function but the main question for now is how other world builders tackle this interesting subject.