Gods walk the Earth and use their power for good or ill. However, being a god does not give you total freedom to do what you want with your power. Gods feed on belief and without belief they can lose access to their powers. Some gods have become so forgotten that they can only cross to our world on special days when belief is higher and barriers are weaker. Halloween may be the time when this is easiest. Not only are the walls between reality weaker, but mortals are more willing to believe in anything on that day.
Since gods feed on belief they can’t ignore their followers too much. Especially, the lesser gods who are nearly forgotten. When a god hears a prayer it must decide whether to ignore it and possibly lose a believer (and thus some power) or to answer it even if it may be to their detriment.
As a side note, because gods feed on belief they have a tendency to like artists, especially writers, whose works can nurture belief, even if it’s a very casual belief.
If you decide to be a god, you must mention your godhood in your high concept.