A question on Mannimarco: We know that in an ending of TESII: Daggerfall (Of course, all the endings are canon thanks to the Warp in the West), he achieves apotheosis with the Numidium, becoming a god (which we know has been his goal since ESO). But, he later appears, in decidedly mortal form, during TESIV: Oblivion. My question is: Was that Mannimarco some incarnation or avatar of the now-divine Altmer? Or is it some other master necromancer that took for himself the name and title of the King of Worms?

A good point. Still, they brought back harpies in pretty nifty fashion in ESO (IMO, of course), and Skyrim did a good job with giants, so I'm still a bit hopeful they can do justice with centaurs.

It was most likely an avatar of his.

Though I'm inclined to agree, there is the minor wiggle of this book, which calls the Necromancer's Moon (supposedly Mannimarco's divine form) the 'God of Worms', rather than the usual 'King of Worms'. This leads me to believe that the Moon and the Altmer seen in Oblivion may not be one and the same. Thoughts?

I'd just like to add in that the Khajiit believe their is a third moon called the Dark Moon or Ghost Moon that they believe is the real body of Lorkhan and not Masser and Secunda.

I know, but I'm not talking about that moon. Supposedly, the Necromancer's Moon orbits the planet Arkay (not the god) in Nirn's solar system, whereas the Dark Moon supposedly is one of Nirn's moons (or so the Khajiit say).

Actually, Planet Arkay is Arkay. Those planets are the flesh of gods. So for example, when you visit Shivering Isles, you walk on Sheogorath, with the guy you are talking to is just an avatar. So, Mannimarco - King of Worms, God of Worms, whatever of Worms - became corpse-planet in mockery of...Arkay was it? Or gods? Help me out here Veloth.

Does it actually orbit Arkay or does it's orbit just obscure Arkay?

Hm, interesting, Tom. Care to elaborate?

According to the UESP, it 'eclipses Arkay and allows soul gems to ensnare those usually protected by the Divine'. Make of that what you will.