Imprint

The Eldest separated Dark and Light, changing the Primordial Chaos into world we know today, dividing realty and unreality. Mortals can no longer shape the world around them as they please. However, the separation wasn't perfect, as that was impossible and, frankly, counterproductive, as it would be equal to lobotomizing all sentient species.
However, this had many side effects, from creation of magic anomalies to beginning of imprint mechanism. Imprints can be described as a faint reminiscence of Primordial Chaos' recreation due to thoughts, now working only for sufficiently powerful daemons residing in the Light, if even partially. Such creatures passively change world around them to better fit their needs.
Such imprints vary. Good example might be dryads, forest queens of Karadia, changing their domains into hard to navigate places of lush and vibrant life, giving lifes to magical creatures like lignomorphs. On the other hand, creatures of evil – servants of Black Pantheon, for example – change their habitat into creepy and terrifying landscape, making ground infertile, twisting plants, letting more poisonous one grow, allowing lesser evil daemons to manifest and twisting the good ones.
Of course such power have limits. Imprints tend to have great problems with overtaking lands already claimed by another imprints, and – especially – towns and villages, that are heavily resistant due to being populated by mortals, possesing souls and thus working as a sort of counter-imprint. Even in lands without towns or another imprints they can't grow infinitely for very simple reason – there are always imprints. Whole world is imprinted by gods, changing for example lands of visenian Lady into idyllic countryside, lands of Inri into place of moral duality where daemons tend to be either good or evil (with neutral much rarer) and so on.
Such 'background' imprints tend to be relatively weak (still extremely powerful considering the fact that beings that created them aren't even in the Light!), but they still work as a sort of an anchor, that stabilizes the world as a whole and prevents various daemons and, especially, aberrants, from taking it over.