The way she is talking combined with Y’Shaarj’s statements that we will die when we leave “this place”, C’Thun’s statements that we are already dead, N’Zoth’s statements that something is behind us and that we should not move not even breathe and the Puzzle Box of Yogg-Saron’s asking us “Do you dream while you sleep or is it an escape from the horrors of reality?” suggest that we are nearing the end of a flashback dream.
In that case N’Zoth is not the one who states that “Only I can save you from what is to come.” but Tyr(who shares a Voice Actor with N’Zoth)!
This throws our confrontation with Odyn to save the Thorignir into question as Xal’atath stated that Odyn was a great enemy until his arrogance proved his undoing. In otherwords it was not Vyranoth who brought us to fight him!
But how are we drowning? For drowning we are.
“It grows hungrier… bolder. Alas, your eyes are closed.” - N’Zoth(Uu’nat Encounter)
The Black Blood is fueled by Wrath. The only being fueled by Wrath is the Harvester of Wrath.
“She is not the last, but the first. Drown her and you will see.” - N’Zoth(Uu’nat Encounter)
Who uses Drowning? The Stonewright!
She is drowning us and is the one who “kills” us in the “Tomb of Sargeras” for daring to desecrate her shrine within Elune’s Temple!
The former Night Warrior Haidene First Priestess of Elune(whose statue is in the place that Xal’atath tells us to desecrate) would dare pass herself as the Goddess in the Dream and Elune ruler of the Dream would mock her for proclaiming herself a “goddess”!
It’s not Xal’atath we are facing but the Night Warrior wanting to use us to kill Haidene for daring to proclaim herself a Goddess while also seeking to claim Azeroth’s World Soul!
The 2nd part of the plan of course fails and Elune is forced to unleash the Night Warrior face upon the Sunwell to make a final grab at the World Soul herself!
That also throws Locus Walker’s questioning Alleria knowing who she is into perspective: Does she know who she is? She seems awfully attached to Khadgar almost like… Jaina!