The Snake is brought up in the Mythos, and here we see it seemingly as a portrayal of deception, and temptation. But many have wondered what exactly it is within Filianism, so let us discuss.
The Snake is described as 'substance without form', meaning it lacks essence. It is the Call of the Abyss, and in the act of deceiving the first daughter it obtained some measure of reality, in that what Snake represents came about as a result of material existence.
But, it still really isn't a 'being' as such. Snake operates more as entropy, pulling on our spirit and souls and trying to ensare us in the kear and sloth, keeping us straying from Dea Herself. Snake is not evil per se, Snake is the dearth of Spirit and the weight of existence which when one dwells upon it, can lead down wrong paths and errant ways of thinking.
Another way to think of Snake would be to compare to Janyatic principles; Snake is the inverse of the Rhavic principle. Sai Rhavë is the principle of restriction and necessary destruction, and the virtue of humility. Snake therefore would be the antithesis of this, rather widespread and frenetic, chaotic destruction, and the inverted virtue, hubris.
When the power of choice came into existence, so too did the choice to make poor decisions that can lead towards what Snake in the Scriptures represents.