I think the only info we really have about New Phyrexia post compleation comes from the story The Lost Confession.
From that story we know that apparently Elesh Norn destroyed Sheoldred's and Urabrask's factions. It's unknown if either Sheoldred or Urabrask are alive, and as far as I'm aware we don't know the status of Jin-Gitaxias's or Vorniclex's factions, presumably they still exist though.
As far as we know, Elesh Norn is nominally in control but all five praetors are still kicking it. OathboundOne has linked the most recent information we have on New Phyrexia outside of Atraxa's Blurb:
Atraxa marks the final victory in the Phyrexian conquest of Mirrodin. Once a Mirran angel who opposed Phyrexia's corruption, she was captured while protecting a Mirran retreat. The praetor Elesh Norn honored her tenacity with the gift of Phyrexian compleation. Jin-Gitaxias, Sheoldred, and Vorinclex all joined Elesh Norn's efforts, and Atraxa was born—a testament to Phyrexia's singular purpose.
Has Vorinclex already been overcome, whats happening with him?
I also heard that Elesh Norn looks to have the biggest forces and the most control if she flexes her muscles.
Is any of this correct, what is going on with the storyline of New Phyrexia!
From that story we know that apparently Elesh Norn destroyed Sheoldred's and Urabrask's factions. It's unknown if either Sheoldred or Urabrask are alive, and as far as I'm aware we don't know the status of Jin-Gitaxias's or Vorniclex's factions, presumably they still exist though.
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