- GODS (IDEAS, SOULS)
- PRIMORDIALS (MATTER, ANIMATION)
- SPIRITS (LIFE)
- ELDERS (CORRUPTION OF MATTER, IDEAS, AND LIFE)
In every given universe, Gods and Primordials coalesce from the raw elements, and are intsantly separated, with the heavier Primordials going towards the bottom of the universe, where the physical elements collide eternally...

Primordials are quintessential compositions of elements, animated more than alive, but filled with force of will focused on creation (sometimes resulting in destruction), and able to forge anything made of their elements with their sole force of will.
...And the Gods floating towards the high heavens, where the etherealness of ideas and souls is at home.
Gods often appear in the shape of their mortal creations, but it's impossible to know their true appearance, because appearance itself is something that is not in their eithereal nature.
Spirits then form where the Primordials and Gods mingle, in their pursuit of recreating themselves through the creation of mortal life in the material worlds. The Spirits are like an inevitable byproduct of life: where there's life, there are spirits, and while they can't create life on their own, they are needed to sustain it, and the more life there is in any given world (to which spirits are confined, this being their limit), the more power the Spirits acquire, becoming able to rival both Primordials and Gods, when their native world is involved. On the contrary, if Life diminishes in some way, the spirits lose their power.

When Spirits of Nature manifest in physical forms, their connection with pure life is always apparent...
Universes are very far from each other, and they spring to life and die during the eons. The so called "Elders", are powerful beings that come from dying or dead universes into younger ones, and are said to be what remains of Gods and/or Primordials of those ruined places. They witnessed the end of all things, and somehow survived it, but they lost everything that matters to them, because in no universe is reality forged in similar ways, so the Elders always find an alien reality in the universes they end up into. And they inevitably want to destroy it all or corrupt it to make it similar to their own.

The shape of Elders is unfathomable for mortals, but even if they descend from Gods and Primordials of other universes, they are themselves mortal when they reach the universe they want to corrupt, since the elements that compose them are different. Even like this, they are as hard to kill as any God or Primordial.
Elders can even corrupt Gods and Primordials, but they can't corrupt Spirits because they're too different in nature. In fact, Elders are never descendents of Spirits of other universes, because Spirits are confined to material worlds, so they never travel outside of them, and they never survive the death of entire universes. But by corrupting Life itself, the Elders "compete" with Spirits and can even eventually kill them.

Where Elders and their creatures walk, nature and life become corrupted or dead, making the Spirits die with them.
Elder-corrupted Primordials are called Demons. They become agents of Destruction, as opposed to their former Primordial nature that was so focused on Creation.

A water primordial corrupted into a water demon lord, existing only to destroy.
Elder-corrupted Gods are very rare, and more often then not, only one God in any given Pantheon (and Universe) becomes courrupted by Elders. Normally, this god then gives rise to Devils, who are corrupted Angels. These corrupted Gods and their Devils corrupt souls and ideas, as opposed to the Primordial-originated Demons dealing only with destruction or corruption of physical matter and flesh.

Elder-corrupted gods combine the majestic and ethereal nature of the gods, with the alien nature of the Elders, becoming opposites of the intelligent concepts that their uncorrupted selves embodied.
Mortal souls are a source of energy for these corrupted and corruptor beings, and they use them to forge new creatures of their kind. The Gods normally reclaim the souls of their mortal creations, but if demons eat them (by force), or devils corrupt them (by temptation), those souls become drops of inexhaustible fuel for the engines of destruction that are the demonic and devilish hells.

Demons and devils from their second generation onwards take on appearances that resemble the mortal souls they are fuelled by, their worst sides in particular.
There are then powerful beings that are related to Spirits, and that can also be corrupted by Elders, but again, they're very rare, because these beings live in parallel worlds, or "world echoes", which are created by the dreams (or nightmares) of the Spirits themselves. These are normally called Feywild (that which originates from Dreams), and Shadowfell (that which originates from Nightmares). They are worlds in which Life is, respectively, heightened or diminished. And they can come into physical contact with the world itself, when the balance of life and powers of a world is in some way changed.
Some Gods and/or Primordials take interest in these parallel worlds, and they make their mortal creations dwell there, and that's how those Spirit-related powerful beings are born.

Beings generally called "Forest Gods" are either Spirit-infused avatars of gods and primordials or their offspring, and contrary to the spirits that gave life to them, they can be corrupted.
Elders of certain types have affinities for some of these world-echoes, probably because in their universe they were tied to one of them. When such an Elder exists, its corruption is often much subtler than that which can happen in the prime material world, because the Gods and Primordials have less power in these Spirit-crafted worlds, so they often can't perceive the corruption, and they become very connected to the Elders themselves. When this happens, Elders often appear in the dreams of mortals, being dreams always connected to the Spirit worlds.
If this kind of corruption is sparked, not even the most knowledgeable Gods can foresee the destruction it can bring to the world.

Corruption is much more dfficult to detect when it targets beings that are more closely connected to life itself.
It is even said, that the gods that take the Spirit Dream world as their favorite, are actually already masked Elders, or Elders that come from a rare universe in which life and reality were visually similar. If this was true, the Fey folk would be the closest thing to a folk created by the Elders themselves, and it would be an agent of destruction more subtle and dangerous than even Demons and Devils.

When the destroyer alien is beautiful, the world that hosts it is doomed...
