Originally Posted by
ThtOneGuy
As far as the Titan constructs go, itt seems that the site of the ToS has significance beyond the fact that the Avatar was interred there. Spoilers obviously:
-Xal'atath tells S-Priests that N'zoth fought and lost a battle against Y'shaarj there
-In the Legion audio drama, Khadgar feels a power within the ToS that is beyond the power of the ancient NEs and Aegwynn.
Given that it has significance to the Old Gods and has a power more ancient than the Highborne, I think it is safe to say that the Titans built that chamber as a means of containment.
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Well, in the Chronicle and Illidan (the book), I think it is stated that demons can actually die in places heavily saturated by the Fel. The Tomb of Sargeras is a massive portal, so, perhaps, he could actually die in the Tomb and is trying to run. Essentially, it is either certainly die in the ToS or maybe die while on the run.