Board Thread:General Discussion/@comment-10197675-20130806142227/@comment-3582098-20140118062425

For the headcanon vs. canon debate- Headcanon is not canon. It can be compared to the film canon of Star Wars vs. the EU Star Wars canon. Anything that the films use from the EU is canon, but until the films use it it is not canonical within the films. However, anything in the films MUST BE canonical within the EU. Similarily, your headcanon MUST contain all canon set in the game, as well as supplimentary material that logically fits within the remainder of the canon already existing. Refuting any part of canon at all renders your headcanon into mere fanfiction rather than headcanon.

Secondly, regarding whether whatever MK writes is canon or not- If it is marked as official by Bethesda, either thorough an official seal of approval, purchase agreement regarding the product, or hiring of him to author a piece, then it is canon. If he writes something within the universe, but it is not accepted into a TES game or other official product, then it is not canon. Any secondary material as such can be headcanon material, assuming it does not directly contradict canon, which if it did would render it merely fan fiction.

Now, onto the topic at hand: I think that Yagrem was already twisted and changed to the point he was not recognizable as a Dwemer when Numidium was activated, given that Vivec, who has supposedly scoured the known universe, but never saw him. I posit that the combination of his fusion with the Dwarven Spider leg assembly and the Corprus disease have twisted him spiritually, given that the Corprus is actually Dagoth Ur's trancendance in Mundus.