Something called the "Crooked Serpent With No Eyes" has been mentioned before, which may have direct relation to Oribos (which is snaked themed through Uroboros and has snake imagery in the structure itself).
It could be the Arbiter, yeah, or it could be something else. The snake imagery is a bit on the nose though.THE END OF ALL THINGS
The crooked serpent with no eyes is watching from the endless sky.
Forked tongues flicker through the black pits in dead stars.
The veil between dream and dreamer slides away like skin from bone.
And even the darkness howls for the light it once despised.
<The rest of the note is illegible, covered in strange glyphs and scribbles.>