What I know so far about the Arbiters is the following:
There were six of them: Order, Evolution, Infinity, Soul, Paradox, and Chaos.
At first, I believed they were aspects of a supreme god who encompassed the entirety of the Superhuman reality. However, recent evidence suggests this may no longer be the case.
In one of the latest updates, there is a record concerning the Arbiter of Chaos. It narrates that the Arbiters faced external enemies, and three of them were killed in battle. These fallen Arbiters transformed into six Twin Apostles. The situation became so dire that the Arbiter of Chaos triggered the Apocalypse Detonator, destroying the entire universe along with himself and the two remaining Arbiters. From this cataclysm, the twelve Apostles, those we know today, came to be.
But who were these enemies?
Ella explains that there are beings capable of entering our universe through the so-called Outer Spheres. Among them, two in particular, referred to as parasites, managed to infiltrate. According to Valravn, these entities exploit the bond between Apostles and the beings of our plane, truly living up to the name parasites. Still, nothing indicates they are the only foreign beings that exist. There may be many others, immensely powerful ones. Who knows?
As for the “Eye,” there are no definitive answers yet, only hints. The strongest theory is that it represents the Arbiter of Evolution. Supporting evidence includes its rejection of the First Apostle’s authority, its complete lack of awe toward the Third and Fourth Apostles who dwell within the MC, and the fact that a monster bowed before it as if it were a true higher authority. Still, nothing is conclusive.
The Eye often declares that it and the MC are one and the same. It also claims it only manifested within the MC because the prerequisites were fulfilled once the MC became a Superhuman. This strongly suggests a connection to Evolution. Yet in the end, it could be something else, another kind of entity, similar to the one inside Henri, or even the very enemy Chaos once annihilated. Imagine that.
Though personally, I doubt it’s the latter, if it were, the monsters would not revere it as their authority. But then again... who can say for certain?