Wicca is duotheist at its centre and expansive at its edges, and both halves of that are deliberate.
At the centre are the Goddess and the God, understood as complementary rather than opposed. The Goddess is associated with the moon and with a threefold form; the God with the sun, the forest and the hunt. Their relationship, and specifically its seasonal course, is the tradition's principal narrative.
That course is a cycle rather than a history. The God is born, comes to maturity, joins with the Goddess, dies and is born again, and the eight festivals of the Wheel of the Year mark the stages. Divine power here is not inherited or seized but annually renewed, and there is no succession between generations because the same figures return.
At the edges, the tradition is openly inclusive. Deities of many pantheons may be invoked, and the widely quoted formulation that all goddesses are one Goddess treats named deities as aspects of the central pair. That is an emanational position and it is why the atlas records the structure as such.
The traffic between human and divine runs downward and is ritual rather than mythological. In drawing down the moon the Goddess is invoked into the priestess, who speaks. A human being is not promoted into the pantheon; the divine is brought into a person for the duration.