TL;DR at the end
Thus far, Treyarch has been hyping up the Warden as the lead antagonist we need to take down to ultimately escape the dark aether. But what if I were to tell you there's something the Warden is keeping at bay that, should he be defeated, will unleash an entity far, far worse?
In the Paradox Junction intro cutscene, he describes himself as a righteous soldier in the dark aether by divine providence. We still don't know exactly how or why he ended up in the dark aether as well as how he managed to strip the shadowsmiths of their free will. But this leads you to wonder, if the shadowsmiths have been there since the earliest days of the dark aether, what created it in the first place? How did it become this realm of primordial chaos?
The Warden believes he needs to create order in a place tainted by the chaos of free will, and I think this lines up directly with an opposing entity that represents the darkest depths of the realm where this corruption and disorder began in the first place. There's a major story factor I'm surprised more people aren't talking about, and it's the fact we know of three different demonic entities thus far.
The biggest one is Nikolai's PTSD moment, confronting the demon that haunted him since the war. We also know Takeo's path of sorrows is directly tied to an evil entity as he's described through its bloodlust. But where this ties in deeper is with the Requiem crew themselves. During Reckoning's main easter egg, carrying the scientist's head results in a smoke-like entity with eyes following the player. It feels out of place and doesn't really make sense at the time, but then the demon that follows us in Nikolai's quest is almost identical in design. This is NOT a coincidence.
The entity, who we now know to be Ava Jansen, said everyone was brought to the dark aether because they were 'touched by a great power', and the Requiem crew assumes it was the sentinel artifact, but I think this ties directly to the demons. These demons don't serve the Warden, so why are they there in the first place? They must be tied to an ancient, possibly eldrich entity of the dark aether that represents pure evil. I think these demons are small instances of its power, and by reducing the Warden's control over the realm, our crew is inadvertently setting it free piece by piece.
Incase you didn't see my theory on the significance of the twins, the teasers we've gotten are extremely reminiscent of the drawings associated with these twins at the Vandorn farm. I'll link it at the end for those interested. Every time the Warden loses a region and a shadowsmith is freed, the twins take hold of that place and become more powerful. It's because of them that the Vandorns go completely insane, and it's this evil that I think ties them directly to the demonic presence as we also know they're in conflict with the Warden.
All in all, there's a lot we don't know yet that Treyarch have been hinting at with these pieces slowly adding up. I think Paradox is going to give us more answers considering the crew has basically been dragged to hell, so no better time to show us there's something truly ancient and evil that wants to create chaos in a world where the Warden is trying to create order. What if this entity is the reason the Warden was brought to the dark aether originally? We're going to start seeing more sides to this story and ultimately, I don't think the Warden will be the big bad we've been made to believe he is.
https://www.reddit.com/r/CODZombies/s/c11MAhKIhA
TL;DR: There's a demonic, eldrich presence deep within the dark aether that wants to bring about chaos in a realm where the Warden is trying to create order, and it may very well be responsible for the corruption that occurs within the dark aether itself. We've seen multiple instances of demons since Reckoning that aren't tied to the Warden, and the inherently evil twins are becoming stronger with each region the Warden loses as the shadowsmiths are freed. We're made to believe the Warden is the ultimate big bad, but if this entity the Warden is holding at bay is freed it could create a far, far worse scenario.