Vosdra has been following the party on a Cloud Ray. She will accost them and try and capture the party alive.
She will show them that she has the same dark mark that they do.
The templar will tell them that they belong to King Nibenay just as she does. That they are brides of Nibenay.
Not just any brides - Shadow Brides - the best of the best. All Templars are brides of Nibenay, But we are above all others - secret to all others.
That their king needs them. That they use his power without being under his command.
The power you have gained is you remembering your former powers. I had hoped you would also regain a memory of you you truly are.
You are men - so i don't know what Nibenay will do.
Dregoth is planning on sending an emissary into the dead lands to find allies in cities rumoured to be to the south. If he gets these allies Athas will run with blood.
If they kill her, her mark will pass to the nearest NPC it sees as a suitable vehicle to regain its templar skills. Once the mark has attached to that NPC then they will have the memories, personality and motivations of the slain templar and will pursue the party. The mark remembers each of its incarnations.