The first ones are the original pantheon
Each one responsible for a cosmic force and the purpose of the pantheon of each force are to keep them in check while the first ones keep the 7th in check
The 7th force is reality and the first one is Azeroth
The other 6 sealed her away for her to be born but over tge millennia the story has been twisted and the purpose has been distorted leading to the Titans believing she's sealed in a prison and they use their constructs and everything else to ensure that she isn't freed
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I think it was linked in a thread on this site but the OP was on a Chinese site
Essentially they are using the themes from previous expansions like Wrath which was death and old god got split to BfA and SL
DF and 11.0 is dragons and elementals so I expect the primalists to open that door