Mythos and the Gods- A General Overview

Alku and the Creation of the Multiverse
The multiverse was made when the formless being Alku solidified out of the nothingness of the primordial ooze. From Alku all things were made: the gods, the material plane and all other planes, good and evil, living beings and immutable truths. Some people say that Alku birthed these things; others say that all these things are part of the whole which is Alku. Alku has no gender, or is all the genders, and Alku's sentience and sentiments are alien to all other beings, even the First Gods (See below). Although Alku is revered and respected, even feared, by most societies, there is little actual worship of Alku because Alku does not ever intervene in the world or the squabbles of lesser beings.
The First Gods
The first beings created from Alku are known as the first gods, and all sentient beings acknowledge their existence, though the worship and the interpretation of each God can vary widely from group to group and individual to individual. These gods are Rayna, the Mother (and Maiden and Crone) Goddess, Aohr, the Father God, Reia, the Goddess of Magic, Irdal, the God of Life and Death, and Phaerean, the Patron of Voyagers.
These gods helped shape Alku into the Multiverse, and it was their alliances and conflicts that shape the material plane. In fact, the name of the world used by most peoples is "Fels Rayna" meaning "Womb of Rayna" or "Land of Rayna" because Rayna (the Goddess of Emotion and Compassion) loves all creatures great and small and is worshipped as the All-Mother, a protective entity who claims all as her own. Her shrines are everywhere and her worship is definitely the most prominent in the world.
Her counterpoint is Aohr, the All-Father whose purview is Tradition and Society, whose basic goal is unity and safety. He is usually worshipped by groups and governments who want to bring people together. He is definitely not as prominent as the other first gods, but he is no less powerful.
Irdal is the God of Life and Death but also of Justice and Duty: although he is sometimes viewed as a dark or sinister figure, or as being cruel or uncaring, Irdal is neither good nor bad: he is the God of Restraint and Reserve.
Irdal's counterpart is Reia, the Goddess of Magic. She is the embodiment of Change and Reason, she is Lady Luck and Lady Wisdom. She represents knowledge, learning, and adaptability, and is particularly favored by spellcasters, magical beings, rogues, and bards.
Lastly, there is Phaerean, the Patron of Voyagers. Phaerean is genderless, and can be referred to by any pronoun. He is the God of Freedom and Individuality, the Goddess of Chaos and Confusion. Some may argue the Phaerean is an evil God, but they are actually just the counterpoint to the sometimes oppressive order of Aohr.
None of the First Gods are good or evil; they are beyond such considerations. While Phaerean is more Chaotic and Aohr is more Lawful, none of the First Gods truly have an alignment. The First Gods rarely interact directly with mortals, instead acting by proxy through lesser gods, dreams, visions and other means. And rather than engage directly with each other in battles or conflicts, they use mortals and lesser gods are proxies.

Lesser Gods
There are a multitude of lesser gods, often changed slightly from one culture to the next as they are given more or less importance or their perceived Domains might change a little. Some of them are viewed as specifically belonging to a certain race, but for the most part, they worshipped by more than one culture. They are numerous and ever changing: however these gods are responsible for most god/mortal interactions.
Heroes and Demigods
A few incredible mortals have been granted a God-like state through their unequaled courage, impossible deeds, or other means. These Heroes are chosen by the First Gods and often dwell on the Plane of Atreos, in great long halls. These Heroes are sometimes worshipped either as mythic ancestors or lesser gods (usually only by their own people or in the place they were from).
Demigods are most often the result of a Deity or similar being mating with a mortal. These beings are sometimes worshipped like gods or heroes but are neither one or the other. They often are mortal but with godlike powers.