Quote Originally Posted by Nilroreo View Post
Exactly! They were only doing what they could for the salvation of their star! They had their worlds shattered by a doomsday event and longed for the world they've lost. They determined that erasure of an entire world is preferable to living in hell. It's as you say, "It was worth it for them if another timeline had a better future."

Btw, can you guess which of the two I've been talking about?
One difference. The people in the 8th Umbral Calamity determined that their OWN erasure was preferable to living in hell. It was not just Ironworks but the survivors in that timeline banding together to work toward the goal of sending the Tower and G'raha back to avert the Calamity.

If the Ancients had stopped with the second sacrifice, it would be the same situation. But they wanted to sacrifice other new lives after the world was restored to a livable state just to get their own people inside Zodiark back.