Conspiracy theory time!
I recently finished building my ESO Lore Library, and I was reading Tamrielic Artifacts, Part Two and came across this except:
"Mehrunes' Razor:
The Dark Brotherhood has coveted this ebony dagger for generations. This mythical artifact is capable of slaying any creature instantly. History does not record any bearers of Mehrunes' Razor. However, the Dark Brotherhood was once decimated by a vicious internal power struggle. It is suspected that the Razor was involved."
Sithis, as we know, is the Embodiment of Change, Chaos, and The Void. He's more of a "Cosmic Force" rather than an Aedra or a Daedra. This is where it gets... Interesting.
I found a book in my travels across Vvardenfell, "The Night Mother's Truth".
"Following the Potentate's assassination in 2E 324, strife descended upon the Morag Tong, and the guild was all but eradicated in Cyrodiil and much of the Empire. It was shortly after these events that the Dunmer woman claimed to hear the voice of Sithis himself. The Dread Lord, she claimed, was displeased. He was unhappy with the Morag Tong's lack of success. The Void, he told her, was hungry for souls—and it was her destiny to set things right."
Well now hang on a minute... Manifesting inside a mortals mind? That's the hallmark of a Daedric Prince.
In another book, "The Blade of Woe":
"My Brothers and Sisters assume we share a single weapon, but how can such a thing be? It has never not appeared when I called for it. The mysteries of our Dread Father, I suppose."
So. The Blade of Woe is 1 weapon, it can kill instantly, it would appear Sithis has a consciousness and he's able to clearly communicate with mortals like a Daedric Prince, and to complicate matters further... At the conclusion of the DB Story in Oblivion, the Blade of Woe that is given to the Hero of Kvatch is "powered up". Daedric Princes have been known to manipulate their artifacts at will. For example, Nocturnal's Cowl.
What's more, Mehrunes Razor belongs to Molag Bal, the Daedric Prince of Destruction. He LOVES collecting souls and enslaving them within Coldharbour. The Slave Pits, the Foundry, the Black Forge, etc. Instead of "sending souls to the Void", what if they're *actually* going to Coldharbour?
I don't know... It kinda makes sense...?